Rate Limits

Overview

RateFlow API enforces two levels of rate limiting:

  1. Per-minute limit — A sliding window that limits how many requests you can make within a 60-second window.
  2. Monthly quota — A fixed monthly allowance that resets on the 1st of each month (UTC).

Both limits are enforced simultaneously. A request must pass both checks to succeed.

Response Headers

Every successful API response includes rate limiting headers:

Header Description
X-RateLimit-Limit Maximum requests allowed per minute on your plan
X-RateLimit-Remaining Requests remaining in the current 60-second window
X-RateLimit-Reset Unix timestamp when the current per-minute window resets
X-Request-ID Unique identifier for the request (useful for support)

When you exceed the monthly quota, the response includes:

Header Description
Retry-After Number of seconds to wait before retrying

Plan Limits

Plan Requests / Month Per-Minute Limit Historical Access
Free 2,000 100 No
Pro 50,000 1,000 Yes (1 year)
Business 300,000 10,000 Yes (unlimited)

{info} Need higher limits? Contact us for a custom Enterprise plan.

Exceeding Limits

When you exceed your rate limit, the API returns a 429 Too Many Requests response:

{
    "type": "https://rateflowapi.com/errors/quota-exceeded",
    "title": "Quota Exceeded",
    "status": 429,
    "detail": "You have exceeded your monthly API quota."
}

Tips to avoid rate limiting:

  • Cache responses on your end (exchange rates typically update once per day).
  • Use the /v1/rates/latest?base=EUR endpoint to get all rates in one call instead of individual pair requests.
  • Monitor your usage with the Quota endpoint or the Dashboard.
  • Upgrade your plan for higher limits at Pricing.