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HTTP 429 Too Many Requests

HTTP 429 Too Many Requests means the client has sent too many requests in a given time (rate limiting). The request contains an error or can’t be fulfilled. Retrying unchanged won’t help.

Class
4xx Client error
Standard
RFC 6585
Cacheable by default
No
Safe to retry
Yes, after the delay in the Retry-After header if present, otherwise with exponential backoff
Go constant
http.StatusTooManyRequests

What HTTP 429 means

The client hit a rate limit. The server can include Retry-After with the number of seconds to wait, and many APIs also send headers like X-RateLimit-Remaining and X-RateLimit-Reset. Well-behaved clients slow down instead of retrying immediately.

How to fix a 429 error

  • Honour Retry-After, and otherwise back off exponentially with jitter (1 s, 2 s, 4 s … plus a random delay).
  • Cache responses and batch requests to make fewer calls.
  • Behind a shared IP (CI runners, NAT), other users may be using up the same limit. Authenticate to get a per-account limit.

Retrying

Yes, after the delay in the Retry-After header if present, otherwise with exponential backoff.

Example response

HTTP/1.1 429 Too Many Requests
Date: Wed, 21 Oct 2026 10:30:00 GMT
Retry-After: 30
X-RateLimit-Limit: 100
X-RateLimit-Remaining: 0
Content-Type: application/json

How to return 429

Node.js (Express)
res.status(429).json({ error: 'Too Many Requests' });
Python (FastAPI)
from fastapi import HTTPException

raise HTTPException(status_code=429, detail="Too Many Requests")
Go (net/http)
http.Error(w, http.StatusText(http.StatusTooManyRequests), http.StatusTooManyRequests)
nginx
location /private/ {
    return 429;
}

Related status codes

Other 4xx status codes

400 Bad Request · 401 Unauthorized · 402 Payment Required · 403 Forbidden · 404 Not Found · 405 Method Not Allowed · 406 Not Acceptable · 407 Proxy Authentication Required · 408 Request Timeout · 409 Conflict · 410 Gone · 411 Length Required · 412 Precondition Failed · 413 Content Too Large · 414 URI Too Long · 415 Unsupported Media Type · 416 Range Not Satisfiable · 417 Expectation Failed · 418 I’m a Teapot · 421 Misdirected Request · 422 Unprocessable Content · 423 Locked · 424 Failed Dependency · 425 Too Early · 426 Upgrade Required · 428 Precondition Required · 431 Request Header Fields Too Large · 444 No Response · 451 Unavailable For Legal Reasons · 499 Client Closed Request

See the full list of HTTP status codes.

Sources

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Frequently asked questions

What does HTTP 429 Too Many Requests mean?

HTTP 429 Too Many Requests means the client has sent too many requests in a given time (rate limiting). The client hit a rate limit. The server can include Retry-After with the number of seconds to wait, and many APIs also send headers like X-RateLimit-Remaining and X-RateLimit-Reset. Well-behaved clients slow down instead of retrying immediately.

How do I fix HTTP 429?

Honour Retry-After, and otherwise back off exponentially with jitter (1 s, 2 s, 4 s … plus a random delay). Cache responses and batch requests to make fewer calls. Behind a shared IP (CI runners, NAT), other users may be using up the same limit. Authenticate to get a per-account limit.