DevArbor
5xx Server Error

507 Insufficient Storage

What it means

Defined in WebDAV (RFC 4918), this indicates the server's storage is full or the storage quota for the resource has been exceeded. The request cannot be completed because there is no room to store the data.

Site Visitor

What can I do?

  • Storage is full. Delete some files to free space before trying again.
Developer

How to debug & fix

  1. Set up disk usage monitoring with alerts at 80% full
  2. Implement per-user storage quotas and return 507 when exceeded
  3. Return the user's current usage and limit in the response body
  4. Set up disk usage alerts at 80% capacity to avoid surprise 507s in production.

Code Example

Node.js / Express
app.post('/files', async (req, res) => {
  const usage = await getStorageUsage(req.user.id);
  if (usage + req.headers['content-length'] > QUOTA) {
    return res.status(507).json({
      error: 'Insufficient Storage',
      usedBytes: usage,
      quotaBytes: QUOTA
    });
  }
});

Related Status Codes

413 Content Too Large 500 Internal Server Error

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 507 Insufficient Storage mean?
Defined in WebDAV (RFC 4918), this indicates the server's storage is full or the storage quota for the resource has been exceeded. The request cannot be completed because there is no room to store the data.
Is HTTP 507 the visitor's fault?
No. HTTP 507 Insufficient Storage is a server-side error. The problem lies with the server, not the visitor. The site owner is responsible for fixing it.
How do I fix HTTP 507 Insufficient Storage?
As a visitor: wait a few minutes and refresh — server errors are usually temporary. As a developer: check your server error logs immediately, restart the application server if needed, and set up uptime monitoring.