HTTP Status Code Lookup
Search every HTTP status code with meanings and fix hints. Searchable reference of all HTTP status codes — 1xx to 5xx — with plain-English meanings, common causes and debugging tips. Free HTTP code lookup.
About the HTTP Status Code Lookup
Is 402 an error? What does 418 really mean? This reference lists every HTTP status class from informational 1xx through client errors 4xx to server errors 5xx, each with a plain-English explanation of when it is sent, the most common causes, and what to check first when you receive it. Filter by class or search by number or keyword — from the everyday 404 to the rarely seen 508.
How to use the HTTP Status Code Lookup
- Type a status number or keyword like "redirect".
- Filter by class if you want to browse a family.
- Click any row to expand causes and fixes.
- Use the search tips when debugging an API response.
Key features
- All standard codes from 100 to 599
- Filter by class or search by number and keyword
- Common causes and first debugging steps
- Includes quirky real codes like 418 and 451
What is the difference between 401 and 403?
Which codes help SEO?
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