API Design · Junior · Question 73 of 75

What do headers like `RateLimit-Remaining` (or `X-RateLimit-Remaining`) give clients?

1The number of active users
✓Correct answer: How many requests are left in the current window, so clients can slow down before hitting 429
3The server's CPU usage

Explanation

Many APIs send limit, remaining and reset values. An IETF draft standardizes RateLimit header fields.

Further reading

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