Why did 413 change its name?
RFC 9110 in 2022 renamed Payload Too Large to Content Too Large, matching the specification's new terminology for message bodies. The code and meaning did not change.
HTTP 413 CONTENT TOO LARGE
The body is bigger than the server accepts. Formerly "Payload Too Large". 413 belongs to the 4xx client error class and is defined in RFC 9110.
Loading the workbench.
About HTTP 413
What Does HTTP 413 Content Too Large Mean?
The body is bigger than the server accepts. Formerly "Payload Too Large". The code is registered with IANA and defined in RFC 9110.
Client error: the request has a problem, so it cannot be fulfilled as sent. Every code from 400 to 499 shares that general meaning, so a client that does not recognise 413 must treat it like 400.
When Do You See a 413 Response?
413 Content Too Large, formerly Payload Too Large, means the request body exceeds what the server is willing to accept. Common sources are nginx's client_max_body_size default of one megabyte, API gateway payload limits, framework body parser limits, and upload size settings in PHP. You typically meet it when uploading images, videos, or large JSON documents. The limit can sit in any layer between the client and the application.
How Do You Fix a 413?
Clients should compress the data, split it into smaller parts, or use a resumable or presigned upload. Server operators should raise the limit in the layer that sent the 413, which may be the proxy rather than the app. If the condition is temporary, include Retry-After. Sending Expect: 100-continue lets a client learn about the limit before transmitting a huge body.
What Does a 413 Response Look Like?
HTTP/1.1 413 Content Too Large
Connection: close
Content-Type: text/html413 is not cacheable by default: a browser or CDN stores it only when Cache-Control or Expires explicitly allows it.
To inspect a real one without sending it anywhere:
- Copy the response headers from your browser Network tab, or from
curl -i. - Paste them into the Header decoder to see every header explained.
- Check caching in the Cache lane.
Which Status Codes Are Related to 413?
- 411 Length Required: The server needs a Content-Length header.
- 414 URI Too Long: The URL is longer than the server will read.
- 431 Request Header Fields Too Large: One header, or all of them together, are too big. Often oversized cookies.
- 100 Continue: The headers were fine; send the body. Used with Expect: 100-continue so a client does not upload a large body that would be rejected.
Browse every code on the HTTP status codes page.
What Other Lanes Are in the Reference Section?
- HTTP status codes: Every IANA-registered status code, with a page per code.
- MIME types: File extensions to Content-Type, searchable both ways, plus a Content-Type parser.
- HTTP methods: GET, POST, PUT, PATCH, DELETE and the rest: safe, idempotent, cacheable.
Elsewhere in 2http: Header decoder, Cookie decoder, Cache-Control decoder, CORS checker, User-agent parser, and all eleven lanes on the 2http home page. Part of the 2suite.io privacy-first ecosystem.
Frequently Asked Questions
Where is the 413 coming from?
Check every layer: CDN, load balancer, nginx or Apache, and the application framework. Each has its own body size limit, and the smallest one wins.
Is HTTP 413 an error?
Yes. 413 is a client error response: the problem is in the request, so repeating it unchanged will usually fail again.
Is a 413 response cacheable by default?
No. Caches store a 413 only when Cache-Control or Expires explicitly allows it.
How Can You Verify That Nothing Leaves This Browser?
You do not have to take our word that your headers stay here. Developer tools show every request a page makes, so you can watch this page work and confirm that nothing is sent. The check takes under a minute.
- Open your browser developer tools with
F12, orCmd+Option+Ion a Mac, and select the Network tab. - Reload the page and let it finish. You will see the page's own files, its web fonts, and one anonymous page-view request. Nothing has been typed yet, so none of them can contain your headers.
- Click the clear icon in the Network tab so that the log is empty.
- Paste real headers into any lane and read the result.
- Look at the Network tab again. It is still empty. For extra proof, turn on offline mode after the page loads and every lane keeps working.
Only two things can add a line to that log, and neither carries your headers. Submitting the feedback form sends the vote and comment you typed. Typing characters in a script the page has not displayed yet, such as Cyrillic or Greek, can make the browser fetch the matching font file, and that request names only the font.
2http never sends a request on your behalf: the request builder writes code for you to run, and the meta inspector reads source you paste instead of fetching a URL. The production site also sends a Content-Security-Policy header that tells your browser to refuse connections to anywhere except this site and the anonymous analytics endpoint.