Rate Limits

API Rate Limits

Rate limits are applied per API key. Limits vary by plan and reset on a sliding window.

Response Headers

Every API response includes headers indicating your current rate limit status.

X-RateLimit-Limit: 60
X-RateLimit-Remaining: 45
X-RateLimit-Reset: 1718191200

Header Definitions

• X-RateLimit-Limit — Maximum requests allowed in the window
• X-RateLimit-Remaining — Requests remaining in the current window
• X-RateLimit-Reset — Unix timestamp when the window resets

Handling 429 Errors

When you exceed the rate limit, the API returns a 429 status code. Use exponential backoff to retry.

async function withRetry<T>(fn: () => Promise<T>, retries = 3): Promise<T> {
  try {
    return await fn();
  } catch (err: any) {
    if (err.status === 429 && retries > 0) {
      const delay = Math.pow(2, 3 - retries) * 1000;
      await new Promise((r) => setTimeout(r, delay));
      return withRetry(fn, retries - 1);
    }
    throw err;
  }
}

import time
 
def with_retry(fn, retries=3):
    try:
        return fn()
    except Exception as e:
        if e.status == 429 and retries > 0:
            delay = 2 ** (3 - retries)
            time.sleep(delay)
            return with_retry(fn, retries - 1)
        raise

Inbox Quotas

In addition to rate limits, there are quotas on the number of active inboxes you can maintain.

Best Practices

• Use webhooks instead of polling when possible
• Cache inbox metadata locally to avoid repeated GET requests
• Implement exponential backoff for all API calls
• Batch operations where the API supports it
• Monitor your usage in the dashboard

Next Steps