OpenAI 401 and 429 Errors: Practical Fix Checklist

OpenAI error guidance lists multiple 401 scenarios, including invalid credentials and IP allowlist mismatch. Treat 401 as a category, not a single root cause.

Start by checking which key is used, which project it belongs to, and whether your request source IP matches project policy.

OpenAI distinguishes at least two common 429 patterns: rate-limit reached and current quota exceeded. The mitigation path is different for each.

If requests are too fast, smooth traffic and retry with backoff. If quota is exceeded, check billing, limits, and project budget settings.

OpenAI rate limits are measured across several dimensions. You can hit RPM first even when TPM still looks healthy, so monitor both request and token dimensions.

Unsuccessful requests still count toward per-minute limits, so repeated immediate retries can worsen incidents.

Use exponential backoff with jitter for retriable failures. Pair retries with request deduplication and timeout budgets to prevent retry storms.

Also tune max_tokens close to expected output size, because rate-limit accounting can depend on max_tokens estimates.

For recurring 401/429 incidents, create a runbook with ownership, alert thresholds, rollback paths, and communication templates.

A short, repeatable checklist is usually more valuable than ad-hoc debugging during peak traffic.