Rate Limits
Understand API rate limits and how to handle them gracefully.
Overview
The YourSend API enforces rate limits to ensure fair usage and system stability. Limits are applied per API key and vary by plan.
Rate Limits by Plan
| Plan | Requests/second | Requests/day |
|---|---|---|
| Starter | 10/s | 10,000 |
| Growth | 50/s | 100,000 |
| Scale | 200/s | 1,000,000 |
Response Headers
Every API response includes rate limit headers:
| Header | Description |
|---|---|
| X-RateLimit-Limit | Maximum requests per window |
| X-RateLimit-Remaining | Remaining requests in current window |
| X-RateLimit-Reset | Unix timestamp when the window resets |
| Retry-After | Seconds to wait (only on 429 responses) |
Handling Rate Limits
When you exceed the rate limit, the API returns a 429 Too Many Requests response. Best practices:
- Implement exponential backoff — Wait progressively longer between retries.
- Check the
Retry-Afterheader — It tells you exactly how long to wait. - Queue messages — For blast campaigns, use the dashboard which handles batching automatically.
- Upgrade your plan — If you consistently hit limits, consider upgrading for higher throughput.