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The rule for 429
A 429 carries a Retry-After header in seconds. Sleep for exactly that long, then retry the request once. Do not retry in a tight loop — that only keeps the window saturated.
Add jitter
If many clients could hit the limit at once, add a small random jitter to the wait so they do not all retry on the same tick and re-trip the limit. A few hundred milliseconds of spread is plenty.
Back off other transient errors
For 5xx responses, use exponential back-off capped at a handful of attempts (e.g. 1s, 2s, 4s, then give up). Do not retry 4xx other than 429 — those are deterministic and will fail again.
Stay under the window
Best of all, keep normal traffic well below 60 requests per 60 seconds per IP — batch, cache and debounce — and you will almost never see a 429. See the rate-limit reference.
Frequently asked questions
How long should I wait after a 429?
Exactly as long as the Retry-After header says, plus a little jitter if you run many clients. Then retry once.
Should I retry a 422 the same way?
No. A 422 is deterministic — it will fail identically. Only retry 429 and transient 5xx responses.
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