HTTP Status Code Lookup
Every common HTTP status code with a plain-English meaning and a practical "what to do about it" from the client developer's side. Type a number or keyword to filter instantly.
AI API tip: when calling LLM APIs, the two codes you will meet most are 429 (rate limit, slow down and retry with exponential backoff plus jitter, and respect the Retry-After header) and 529 (Anthropic's "overloaded" code, the service itself is saturated, retry with backoff the same way). Treat 5xx as retryable and most 4xx as bugs in your request that retrying will not fix. Status semantics follow RFC 9110; a few entries (like 529) are provider-specific conventions.