{"id":399,"date":"2022-07-25T10:36:47","date_gmt":"2022-07-25T10:36:47","guid":{"rendered":"https:\/\/www.testleaf.com\/blog\/?p=399"},"modified":"2026-03-06T13:21:05","modified_gmt":"2026-03-06T07:51:05","slug":"most-common-used-http-response-status-codes","status":"publish","type":"post","link":"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/","title":{"rendered":"Most Common Used HTTP response status codes"},"content":{"rendered":"<div style=\"margin-top: 0px; margin-bottom: 0px;\" class=\"sharethis-inline-share-buttons\" ><\/div><!--[if lt IE 9]><script>document.createElement('audio');<\/script><![endif]-->\n<audio class=\"wp-audio-shortcode\" id=\"audio-399-1\" preload=\"none\" style=\"width: 100%;\" controls=\"controls\"><source type=\"audio\/mpeg\" src=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2022\/07\/Most-Common-Used-HTTP-response-status-codes.mp3?_=1\" \/><a href=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2022\/07\/Most-Common-Used-HTTP-response-status-codes.mp3\">https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2022\/07\/Most-Common-Used-HTTP-response-status-codes.mp3<\/a><\/audio>\n<p>&nbsp;<\/p>\n<p data-start=\"1708\" data-end=\"2076\">HTTP status codes show whether a request succeeded, was redirected, failed due to the client, or failed on the server. In API testing, they help you validate expected behavior (200\/201), detect auth issues (401\/403), data problems (400\/404), rate limits (429), and outages\/timeouts (502\/503\/504). Always assert the code and the error body.<\/p>\n<h2 data-start=\"2078\" data-end=\"2114\"><span class=\"ez-toc-section\" id=\"Key_Takeaways\"><\/span><strong>Key Takeaways\u00a0<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2><div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Key_Takeaways\" >Key Takeaways\u00a0<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Information_responses\" >Information responses<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Successful_responses\" >Successful responses<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Redirection_messages\" >Redirection messages<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Client_error_responses\" >Client error responses<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#Server_error_responses\" >Server error responses<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/#FAQs\" >FAQs<\/a><\/li><\/ul><\/nav><\/div>\n\n<p data-start=\"2115\" data-end=\"2155\"><strong data-start=\"2115\" data-end=\"2125\">Place:<\/strong> Immediately after Answer Box.<\/p>\n<ul data-start=\"2156\" data-end=\"2397\">\n<li data-start=\"2156\" data-end=\"2240\">\n<p data-start=\"2158\" data-end=\"2240\">Validate both <strong data-start=\"2172\" data-end=\"2203\">status code + response body<\/strong> (error message, fields, trace id).<\/p>\n<\/li>\n<li data-start=\"2241\" data-end=\"2316\">\n<p data-start=\"2243\" data-end=\"2316\">Most debugging starts with <strong data-start=\"2270\" data-end=\"2296\">401\/403, 404, 429, 5xx<\/strong> in real projects.<\/p>\n<\/li>\n<li data-start=\"2317\" data-end=\"2397\">\n<p data-start=\"2319\" data-end=\"2397\">In CI, treat <strong data-start=\"2332\" data-end=\"2347\">502\/503\/504<\/strong> as reliability signals (retries + observability).<\/p>\n<\/li>\n<\/ul>\n<p>In India\/global CI regions, network latency and gateway routing can increase timeouts\u2014so 502\/503\/504 may appear more often in cloud runners. Validate Retry-After headers, use sane timeouts, and capture request\/trace IDs for faster triage.<\/p>\n<p>HTTP response status codes indicate whether a specific\u00a0<a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\"><u>HTTP<\/u><\/a>\u00a0request has been completed. Responses are grouped into five classes:<\/p>\n<p>&nbsp;<\/p>\n<p><strong><b>Note:<\/b><\/strong><br \/>\nIf you receive a response that is not on\u00a0<a href=\"#information-responses\"><u>this list<\/u><\/a>, it is a non-standard response, possibly custom developed.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Information_responses\"><\/span><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status#information_responses\" target=\"_blank\" rel=\"noopener\">Information responses<\/a><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/100target=\">100 Continue<\/a><\/strong><br \/>\nThis interim response indicates that the client should continue the request or ignore the response if the request is already finished.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/102\" target=\"_blank\" rel=\"noopener\">102 Processing<\/a>\u00a0(<a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Glossary\/WebDAV\" target=\"_blank\" rel=\"noopener\"><u>WebDAV<\/u><\/a>)<\/strong><br \/>\nThis code indicates that the server has received and is processing the request, but no response is available.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Successful_responses\"><\/span><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status#successful_responses\" target=\"_blank\" rel=\"noopener\">Successful responses<\/a><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/200\" target=\"_blank\" rel=\"noopener\">200 OK<\/a><\/strong><br \/>\nThe request succeeded. The result meaning of &#8220;success&#8221; depends on the HTTP method:<\/p>\n<ul>\n<li>GET: The resource has been fetched and transmitted in the message body.<\/li>\n<li>HEAD: The representation headers are included in the response without any message body.<\/li>\n<li>PUTor\u00a0POST: The resource describing the result of the action is transmitted in the message body.<\/li>\n<li>TRACE: The message body contains the request message as received by the server.<\/li>\n<\/ul>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/201\" target=\"_blank\" rel=\"noopener\">201 Created<\/a><\/strong><br \/>\nThe request succeeded, and a new resource was created as a result. This is typically the response sent after\u00a0POST\u00a0requests, or some\u00a0PUT\u00a0requests.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/204\" target=\"_blank\" rel=\"noopener\">204 No Content<\/a><\/strong><br \/>\nThere is no content to send for this request, but the headers may be useful. The user agent may update its cached headers for this resource with the new ones.<\/p>\n<p><a href=\"https:\/\/ai-master-class.testleaf.com\/?utm_source=GenAI_Webinar&amp;utm_medium=Organic&amp;utm_campaign=GenAI_Webinar_Blog\"><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter wp-image-8828 size-full\" src=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass.png\" alt=\"Gen AI Masterclass\" width=\"2048\" height=\"512\" srcset=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass.png 2048w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass-300x75.png 300w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass-1024x256.png 1024w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass-768x192.png 768w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass-1536x384.png 1536w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2026\/01\/Gen-AI-Masterclass-150x38.png 150w\" sizes=\"(max-width: 2048px) 100vw, 2048px\" \/><\/a><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Redirection_messages\"><\/span><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status#redirection_messages\" target=\"_blank\" rel=\"noopener\">Redirection messages<\/a><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/301\" target=\"_blank\" rel=\"noopener\">301 Moved Permanently<\/a><\/strong><br \/>\nThe URL of the requested resource has been changed permanently. The new URL is given in the response.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Client_error_responses\"><\/span><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status#client_error_responses\" target=\"_blank\" rel=\"noopener\">Client error responses<\/a><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/400\" target=\"_blank\" rel=\"noopener\"><strong>400 Bad Request<\/strong><\/a><br \/>\nThe server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/401\" target=\"_blank\" rel=\"noopener\">401 Unauthorized<\/a><\/strong><br \/>\nAlthough the HTTP standard specifies &#8220;unauthorized&#8221;, semantically this response means &#8220;unauthenticated&#8221;. That is, the client must authenticate itself to get the requested response.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/403\" target=\"_blank\" rel=\"noopener\">403 Forbidden<\/a><\/strong><br \/>\nThe client does not have access rights to the content; that is, it is unauthorized, so the server is refusing to give the requested resource. Unlike\u00a0401 Unauthorized, the client&#8217;s identity is known to the server.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/404\" target=\"_blank\" rel=\"noopener\">404 Not Found<\/a><\/strong><br \/>\nThe server can not find the requested resource. In the browser, this means the URL is not recognized. In an API, this can also mean that the endpoint is valid but the resource itself does not exist. Servers may also send this response instead of\u00a0403 Forbidden\u00a0to hide the existence of a resource from an unauthorized client. This response code is probably the most well known due to its frequent occurrence on the web.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/405\" target=\"_blank\" rel=\"noopener\">405 Method Not Allowed<\/a><\/strong><br \/>\nThe request method is known by the server but is not supported by the target resource. For example, an API may not allow calling\u00a0DELETE\u00a0to remove a resource.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/408\" target=\"_blank\" rel=\"noopener\">408 Request Timeout<\/a><\/strong><br \/>\nThis response is sent on an idle connection by some servers, even without any previous request by the client. It means that the server would like to shut down this unused connection. This response is used much more since some browsers, like Chrome, Firefox 27+, or IE9, use HTTP pre-connection mechanisms to speed up surfing. Also note that some servers merely shut down the connection without sending this message.<\/p>\n<p><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/413\" target=\"_blank\" rel=\"noopener\"><strong>413 Payload Too Large<\/strong><\/a><br \/>\nRequest entity is larger than limits defined by server. The server might close the connection or return an\u00a0Retry-After\u00a0header field.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/414\" target=\"_blank\" rel=\"noopener\">414 URI Too Long<\/a><\/strong><br \/>\nThe URI requested by the client is longer than the server is willing to interpret.<\/p>\n<p><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/415\" target=\"_blank\" rel=\"noopener\"><strong>415 Unsupported Media Type<\/strong><\/a><br \/>\nThe media format of the requested data is not supported by the server, so the server is rejecting the request.<\/p>\n<p><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/429\" target=\"_blank\" rel=\"noopener\"><strong>429 Too Many Requests<\/strong><\/a><br \/>\nThe user has sent too many requests in a given amount of time (&#8220;rate limiting&#8221;).<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Server_error_responses\"><\/span><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status#server_error_responses\" target=\"_blank\" rel=\"noopener\">Server error responses<\/a><\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/500\" target=\"_blank\" rel=\"noopener\">500 Internal Server Error<\/a><\/strong><br \/>\nThe server has encountered a situation it does not know how to handle.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/502\" target=\"_blank\" rel=\"noopener\">502 Bad Gateway<\/a><\/strong><br \/>\nThis error response means that the server, while working as a gateway to get a response needed to handle the request, got an invalid response.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/503\" target=\"_blank\" rel=\"noopener\">503 Service Unavailable<\/a><\/strong><br \/>\nThe server is not ready to handle the request. Common causes are a server that is down for maintenance or that is overloaded. Note that together with this response, a user-friendly page explaining the problem should be sent. This response should be used for temporary conditions and the\u00a0Retry-After\u00a0HTTP header should, if possible, contain the estimated time before the recovery of the service. The webmaster must also take care about the caching-related headers that are sent along with this response, as these temporary condition responses should usually not be cached.<\/p>\n<p><strong><a href=\"https:\/\/developer.mozilla.org\/en-US\/docs\/Web\/HTTP\/Status\/504\" target=\"_blank\" rel=\"noopener\">504 Gateway Timeout<\/a><\/strong><br \/>\nThis error response is given when the server is acting as a gateway and cannot get a response in time.<\/p>\n<h3><strong>Wrapping Up<\/strong><\/h3>\n<p>In this article, we have covered the most popular HTTP response status codes that are used. You can use the information provided to understand HTTP status codes and respond accordingly. We hope you found this article helpful. For more information, please visit <a href=\"https:\/\/www.testleaf.com\/course\/rest-api-testing-certification-training-course.html\"><u>REST API Testing Training in Chennai<\/u><\/a>\u00a0.<\/p>\n<p>&nbsp;<\/p>\n<h2 data-start=\"3497\" data-end=\"3545\"><span class=\"ez-toc-section\" id=\"FAQs\"><\/span><strong>FAQs<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\t<div class=\"tlfaq\" id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274\"\n\t     data-single-open=\"1\">\n\t\t\n\t\t<div class=\"tlfaq__items\" role=\"region\" aria-label=\"FAQ\">\n\t\t\t\t\t\t\t<details class=\"tlfaq__item\" open id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-0\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">What is the difference between 401 and 403?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\t401 Unauthorized means the request is not authenticated, usually because the token is missing or invalid. 403 Forbidden means the request is authenticated, but the user does not have permission to access that resource.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-1\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">What does 404 mean in API testing?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\tA 404 status code can mean the endpoint URL is incorrect, or the endpoint exists but the requested resource ID is not found. In API testing, verify the route and test again with a known valid resource ID.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-2\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">What should I do when an API returns 400 Bad Request?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\tWhen an API returns 400 Bad Request, check the request payload format, required fields, content type, and schema validation rules. It is also a good practice to add negative tests to verify that the error message is meaningful.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-3\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">What does 429 Too Many Requests mean?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\t429 Too Many Requests indicates that the API rate limit has been exceeded. In testing, verify throttling behavior and respect backoff instructions such as the Retry-After header if it is provided.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-4\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">What\u2019s the difference between 502, 503, and 504?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\t502 means the gateway received an invalid response from the upstream server. 503 means the service is unavailable due to overload or maintenance. 504 means the gateway timed out while waiting for the upstream server. In testing, capture timestamps and trace IDs for better debugging.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-5\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">Why do I get 204 No Content?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\t204 No Content means the request was successful but there is no response body. This is common for delete or update operations. Tests should validate response headers and confirm state changes with a follow-up GET request.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t\t\t<details class=\"tlfaq__item\"  id=\"tlfaq-3b26ea11-2c66-469e-b4e5-0690474a0274-6\">\n\t\t\t\t\t<summary class=\"tlfaq__question\">\n\t\t\t\t\t\t<span class=\"tlfaq__qtext\">Can 404 be used for security?<\/span>\n\t\t\t\t\t\t<span class=\"tlfaq__icon\" aria-hidden=\"true\"><\/span>\n\t\t\t\t\t<\/summary>\n\t\t\t\t\t<div class=\"tlfaq__answer\">\n\t\t\t\t\t\tYes. Some systems intentionally return 404 instead of 403 to hide the existence of protected resources from unauthorized users.\t\t\t\t\t<\/div>\n\t\t\t\t<\/details>\n\t\t\t\t\t\t<\/div>\n\n\t\t\t\t\t<script type=\"application\/ld+json\">\n\t\t\t\t{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"What is the difference between 401 and 403?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"401 Unauthorized means the request is not authenticated, usually because the token is missing or invalid. 403 Forbidden means the request is authenticated, but the user does not have permission to access that resource.\"}},{\"@type\":\"Question\",\"name\":\"What does 404 mean in API testing?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A 404 status code can mean the endpoint URL is incorrect, or the endpoint exists but the requested resource ID is not found. In API testing, verify the route and test again with a known valid resource ID.\"}},{\"@type\":\"Question\",\"name\":\"What should I do when an API returns 400 Bad Request?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"When an API returns 400 Bad Request, check the request payload format, required fields, content type, and schema validation rules. It is also a good practice to add negative tests to verify that the error message is meaningful.\"}},{\"@type\":\"Question\",\"name\":\"What does 429 Too Many Requests mean?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"429 Too Many Requests indicates that the API rate limit has been exceeded. In testing, verify throttling behavior and respect backoff instructions such as the Retry-After header if it is provided.\"}},{\"@type\":\"Question\",\"name\":\"What\u2019s the difference between 502, 503, and 504?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"502 means the gateway received an invalid response from the upstream server. 503 means the service is unavailable due to overload or maintenance. 504 means the gateway timed out while waiting for the upstream server. In testing, capture timestamps and trace IDs for better debugging.\"}},{\"@type\":\"Question\",\"name\":\"Why do I get 204 No Content?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"204 No Content means the request was successful but there is no response body. This is common for delete or update operations. Tests should validate response headers and confirm state changes with a follow-up GET request.\"}},{\"@type\":\"Question\",\"name\":\"Can 404 be used for security?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. Some systems intentionally return 404 instead of 403 to hide the existence of protected resources from unauthorized users.\"}}]}\t\t\t<\/script>\n\t\t\t<\/div>\n\t\n<h5><strong>We Also Provide Training In:<\/strong><\/h5>\n<ul>\n<li><a href=\"https:\/\/www.testleaf.com\/course\/selenium-automation-certification-training-course.html?utm_source=blog_post&amp;utm_medium=Organic&amp;utm_campaign=Blog_Post\"><strong>Advanced Selenium Training<\/strong><\/a><\/li>\n<li><a href=\"https:\/\/www.testleaf.com\/course\/playwright.html?utm_source=blog-post&amp;utm_medium=Organic&amp;utm_campaign=Blog_Post\"><strong>Playwright Training<\/strong><\/a><\/li>\n<li><a href=\"https:\/\/www.testleaf.com\/course\/genai-qa-engineers-training-course.html?utm_source=blog-post&amp;utm_medium=Organic&amp;utm_campaign=Blog_Post\"><strong>Gen AI Training<\/strong><\/a><\/li>\n<li><a 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elementor-element-populated\">\n<div class=\"elementor-element elementor-element-adb33d7 elementor-widget elementor-widget-heading\" data-id=\"adb33d7\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n<div class=\"elementor-widget-container\">\n<h6 class=\"elementor-heading-title elementor-size-default\">Author\u2019s Bio:<\/h6>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<section class=\"elementor-section elementor-top-section elementor-element elementor-element-dcde5ac elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"dcde5ac\" data-element_type=\"section\">\n<div class=\"elementor-container elementor-column-gap-default\">\n<div class=\"elementor-column elementor-col-33 elementor-top-column elementor-element elementor-element-4320106\" data-id=\"4320106\" data-element_type=\"column\">\n<div class=\"elementor-widget-wrap elementor-element-populated\">\n<div class=\"elementor-element elementor-element-a109ac0 elementor-widget elementor-widget-image\" data-id=\"a109ac0\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n<div class=\"elementor-widget-container\"><img decoding=\"async\" class=\"attachment-large size-large wp-image-2404\" src=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2023\/04\/Untitled-design.png\" sizes=\"(max-width: 250px) 100vw, 250px\" srcset=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2023\/04\/Untitled-design.png 250w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2023\/04\/Untitled-design-150x150.png 150w, https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2023\/04\/Untitled-design-96x96.png 96w\" alt=\"\" width=\"250\" height=\"250\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"elementor-column elementor-col-66 elementor-top-column elementor-element elementor-element-bff9339\" data-id=\"bff9339\" data-element_type=\"column\">\n<div class=\"elementor-widget-wrap elementor-element-populated\">\n<div class=\"elementor-element elementor-element-fa38e39 elementor-widget elementor-widget-text-editor\" data-id=\"fa38e39\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n<div class=\"elementor-widget-container\">\n<p>As CEO of TestLeaf, I\u2019m dedicated to transforming software testing by empowering individuals with real-world skills and advanced technology. With 24+ years in software engineering, I lead our mission to shape local talent into global software professionals. Join us in redefining the future of test engineering and making a lasting impact in the tech world.<\/p>\n<p>Babu Manickam<\/p>\n<p>CEO \u2013 Testleaf<br \/>\n<a href=\"https:\/\/in.linkedin.com\/in\/babu-manickam\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"https:\/\/www.testleaf.com\/blog\/wp-content\/uploads\/2024\/12\/linkedin.png\" alt=\"LinkedIn Logo\" width=\"28\" height=\"28\" \/><\/a><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<h6><\/h6>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; HTTP status codes show whether a request succeeded, was redirected, failed due to the client, or failed on the server. In API testing, they help you validate expected behavior (200\/201), detect auth issues (401\/403), data problems (400\/404), rate limits (429), and outages\/timeouts (502\/503\/504). Always assert the code and the error body. Key Takeaways\u00a0 Place: &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/www.testleaf.com\/blog\/most-common-used-http-response-status-codes\/\"> <span class=\"screen-reader-text\">Most Common Used HTTP response status codes<\/span> Read More &raquo;<\/a><\/p>\n","protected":false},"author":1,"featured_media":401,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"site-sidebar-layout":"right-sidebar","site-content-layout":"plain-container","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","footnotes":""},"categories":[6],"tags":[],"class_list":["post-399","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-general"],"acf":[],"aioseo_notices":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/posts\/399","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/comments?post=399"}],"version-history":[{"count":61,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/posts\/399\/revisions"}],"predecessor-version":[{"id":9470,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/posts\/399\/revisions\/9470"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/media\/401"}],"wp:attachment":[{"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/media?parent=399"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/categories?post=399"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.testleaf.com\/blog\/wp-json\/wp\/v2\/tags?post=399"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}