Rate Limits

Per-Tier Limits

Sliding Window Algorithm

Rate limits use a 60-second sliding window per API key. The window moves continuously—there is no fixed reset boundary. If you send 100 requests at second 0 and wait 30 seconds, you will have approximately 50 requests available as the oldest requests age out of the window.

Rate Limit Headers

Every API response includes three headers that describe your current rate limit status:

Handling 429 Responses

When you exceed the rate limit, the API returns a 429 Too Many Requests response with a Retry-After header indicating how many seconds to wait:

{
  "error": {
    "status": 429,
    "message": "Rate limit exceeded. Retry after 12 seconds.",
    "requestId": "req_abc123def456"
  }
}

// Response headers:
// Retry-After: 12
// X-RateLimit-Limit: 100
// X-RateLimit-Remaining: 0
// X-RateLimit-Reset: 1711843200

Retry Strategy

Implement exponential backoff with the Retry-After header as your baseline:

async function fetchWithRetry(url: string, options: RequestInit, maxRetries = 3) {
  for (let attempt = 0; attempt <= maxRetries; attempt++) {
    const response = await fetch(url, options);

    if (response.status !== 429) return response;

    const retryAfter = parseInt(response.headers.get("Retry-After") ?? "5", 10);
    const backoff = retryAfter * Math.pow(2, attempt);
    await new Promise((resolve) => setTimeout(resolve, backoff * 1000));
  }

  throw new Error("Rate limit exceeded after max retries");
}

Server-Side Caching

Responses are cached server-side with per-route TTLs. The X-Cache header indicates whether the response was served from cache. Cached responses still count toward your monthly quota.