Free tier
Which models are free, the daily limits per account, and the 429 when they run out.
A model is free on Rapid Router when its provider charges us nothing for it, and then it is free to you too. Nothing else is sponsored: every other model is billed at the provider's price. Older ids ending in :free that are no longer free are not listed: they still answer, billed the same as the model without :free. A free request bills $0, works with a zero balance, and goes through the same routing, streaming and logging as everything else. Models that can be called free carry "variants": ["free"] in GET /models; using :free on any other model returns 400.
Limits are per account, per UTC day: 50 free requests a day, raised to 1,000 once your lifetime paid usage reaches $10. Going over returns 429 with code free_tier_exhausted; the counter resets at midnight UTC. Rate limits and the concurrency ceiling still apply.
A free model whose catalog id itself ends in :free (tagged Free on the models page, priced $0) counts against the same per-account limit, images one each. Should we ever price a model at $0 that its provider bills us for, its requests also share a platform-wide daily limit, which resets at midnight IST; when that is reached it returns 429 with code free_pool_exhausted until the reset.
curl https://rapidrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $RAPIDROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/gemma-4-31b-it:free",
"messages": [{ "role": "user", "content": "Hi" }]
}'
# usage.cost is 0. No credits are debited.