DevArbor
4xx Client Error

416 Range Not Satisfiable

What it means

The server cannot satisfy the Range request header. Either the range is outside the file's actual size, the range values are invalid, or the resource doesn't support range requests. The response should include Content-Range with the total file size.

Site Visitor

What can I do?

  • Try downloading the file fresh from the beginning.
  • If the problem persists after retrying, contact the site owner.
Developer

How to debug & fix

  1. Always validate Range values against actual content length
  2. Return Content-Range: bytes */total_size in 416 responses
  3. Handle the edge case where a resumed download finds a changed file
  4. Review the RFC for this status code for precise semantics before implementation.

Code Example

Node.js / Express
if (start >= totalSize) {
  return res.status(416)
    .set('Content-Range', `bytes */${totalSize}`)
    .end();
}

Related Status Codes

206 Partial Content

How HTTP Status Codes Work

Every HTTP response carries a three-digit status code that tells the client — browser, API consumer, or search-engine crawler — exactly what happened. The first digit defines the class: 1xx informational (request in progress), 2xx success, 3xx redirection, 4xx client error (bad request, missing auth, not found), and 5xx server failure.

Status codes are standardised in RFC 9110 (HTTP Semantics, 2022). Extensions like WebDAV (RFC 4918) and rate-limit headers (RFC 6585) added codes beyond the core set. When a client receives an unrecognised code, the rule is to treat it as the generic x00 of its class.

Why the Right Code Matters

Semantically correct codes help search engines index accurately (301 passes link equity; 410 removes pages faster than 404), allow API clients to implement correct retry logic (429 + Retry-After, 503 + Retry-After), and let monitoring systems distinguish bugs (500) from load issues (503) from auth failures (401/403).

Looking up a different status code? The full reference covers all HTTP codes with causes, fix guides, and copyable code examples for Node.js and Python.

Browse the full HTTP Status Code reference →

Frequently Asked Questions

What does HTTP 416 Range Not Satisfiable mean?
The server cannot satisfy the Range request header. Either the range is outside the file's actual size, the range values are invalid, or the resource doesn't support range requests. The response should include Content-Range with the total file size.
Is HTTP 416 the visitor's fault?
HTTP 416 Range Not Satisfiable is generally a client-side error, meaning the request itself has an issue. However, many causes — such as a broken link on the site or a misconfigured redirect — are the website owner's responsibility, not the visitor's.
How do I fix HTTP 416 Range Not Satisfiable?
As a visitor: check the URL for typos, go to the homepage, or search for the content. As a developer: always validate Range values against actual content length.