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Rate Limits

ThumbAPI enforces two types of limits: monthly credit quotas and per-second rate limits.

Monthly Credit Quotas

Pricing is metered in credits. A standard 1K thumbnail costs 10 credits; add-ons (usePhoto, useLogo, customAssetsId) add +2 each; a 2K (hd) render costs 20 credits instead of 10. See credit cost details.

PlanCredits / MonthPriceStandard 1K thumbnails*
Free50$0~5
Creator750$19/month~75
Pro2,500$49/month~250
Business10,000$199/month~1,000

*Approximate count assumes base 1K renders with no add-ons. Actual count depends on the mix of sd/hd and add-on flags you use.

Credits reset on the first day of each billing period. Unused credits do not roll over.

Free-tier output carries a small ThumbAPI watermark; Creator and higher plans return watermark-free images.

Rate Limits

PlanRequests / Second
Free1
Creator2
Pro5
Business20

Rate limits apply per API key.

Response Headers

Every response includes credit-quota information:

X-RateLimit-Limit: 2500
X-RateLimit-Remaining: 1847
X-RateLimit-Reset: 2026-05-01T00:00:00Z
HeaderDescription
X-RateLimit-LimitTotal credits allowed this billing period
X-RateLimit-RemainingCredits remaining this billing period
X-RateLimit-ResetWhen the quota resets (ISO 8601)

When You Hit a Limit

Credit quota exceeded: HTTP 429 with "Generation limit exceeded". Wait for the next billing period or upgrade your plan.

Per-second rate limit exceeded: HTTP 429 with "Rate limit exceeded". Implement backoff and retry.

Best Practices

  1. Check X-RateLimit-Remaining before making requests in batch jobs
  2. Implement exponential backoff for 429 responses (see Error Codes)
  3. Cache generated thumbnails — don't regenerate the same title twice
  4. Use webhooks (Pro+) for async generation instead of polling

Upgrading

Upgrade your plan at any time from the dashboard. Changes take effect immediately — no proration for the current period.

Next Steps