# OpenAI API Error 429: Rate Limit or Quota Exceeded

TL;DR: OpenAI API error 429 means the API rejected the request because the account, project, model, or organization is over a rate or quota limit.

Target query: OpenAI API error 429 rate limit
Likely fault area: mixed
Run diagnosis: https://llmping.app/#diagnose

## What this error means

OpenAI API 429 usually means your request is being rate limited, your quota is exhausted, or your project has hit a per-minute token/request cap.

## Is it code, key, rate limit, or server-side?

Category: rate_limit
Likely fault area: mixed

## Immediate checklist

- Check whether the response body says rate_limit_exceeded, insufficient_quota, or billing_hard_limit_reached.
- Verify the project and organization attached to the API key.
- Look at requests per minute, tokens per minute, and daily/monthly spend limits separately.
- Retry only with exponential backoff and jitter; do not loop immediately.

## cURL test command

```bash
curl https://api.openai.com/v1/models \
  -H "Authorization: Bearer $OPENAI_API_KEY"
```

## Common fixes

- Reduce concurrency and batch size first; most 429 loops are caused by parallel workers.
- Use exponential backoff with jitter and respect Retry-After when the header is present.
- Switch low-priority traffic to a cheaper or smaller model during spikes.
- Increase project limits or add billing if the error body says quota rather than rate limit.

## Related errors

- https://llmping.app/errors/openai/401/
- https://llmping.app/errors/openai/403/
- https://llmping.app/status/openai/