All HTTP status codes

HTTP 429 Too Many Requests

Client Error

The client exceeded the rate limit. The Retry-After header (when present) says how long to back off.

Defined in RFC 6585

Common causes

  • Burst traffic beyond API quotas
  • Missing client-side throttling or runaway retry loops
  • Shared IPs (NAT, serverless egress) pooling many users into one limit

How to fix it

  1. Honor Retry-After and implement exponential backoff with jitter

  2. Batch or cache requests client-side

  3. Ask the provider for higher limits or per-key quotas

Related status codes

402 Payment Required

Reserved originally for digital payments; today used by some APIs to signal exceeded quotas, expired subscriptions, or billing problems.

503 Service Unavailable

The server is temporarily unable to handle the request — overloaded, in maintenance, or deliberately shedding load. Retry-After may say when to come back.

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