API Rate Limits

WhiteBooks throttles at the gateway. Sandbox is fixed at 60 req/min/key. Production rate limits scale by plan tier and burst over short windows. 429 responses always include a Retry-After header in seconds.

Per-tier limits

TierSteady-stateBurst (10s)Monthly volume cap
Sandbox60 req/min/key——
Starter100 req/s200 req/s1,000 IRN / EWB per month
Growth200 req/s500 req/s5,000 IRN / EWB per month
Business1,000 req/s2,000 req/s25,000 IRN / EWB per month
EnterpriseBurstable / negotiatedNegotiatedUnlimited

Handling 429

HTTP/1.1 429 Too Many Requests
Retry-After: 12
Content-Type: application/json

{ "status": 429, "code": "RATE_LIMIT_EXCEEDED", "message": "..." }

SDKs handle 429 automatically — they honour Retry-After, sleep, then retry up to 3 times before surfacing the error to your code.

Bulk endpoints

Bulk endpoints (/bulk-generate-irn, /bulk-generate) count as a SINGLE call against your rate limit regardless of payload size (up to 1,000 entries per call). They're the cheapest way to process high volume.

Error codes →Full error reference Retry logic →How SDKs handle 429 + 5xx Pricing →Per-tier IRN/EWB volumes Status →Live throughput numbers

Part of the WhiteBooks developer documentation cluster. See /llms.txt for the full machine-readable site index. Last updated 27 May 2026.

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