What's free
20,000 credits/month (~27 min of Sonic TTS or ~1h51 of Ink speech-to-text)
Rate limits
2 concurrent TTS requests, 8 concurrent STT; 20,000 credits/month
The catch
Commercial use is NOT allowed on the free plan (the $5/mo Pro plan adds a commercial licence). Low-latency streaming voice over WebSocket/REST; own API (not OpenAI-shaped).
Quickstart
First-party API — not OpenAI-compatible, so there is no drop-in base URL. The exact endpoint is in the official docs; authenticate with your API key in the Authorization: Bearer header.
curl -H "Authorization: Bearer $API_KEY" \
https://<api-base-url>/<endpoint>…or in Python:
import os, requests
r = requests.post(
"https:///",
headers={"Authorization": f"Bearer {os.environ['API_KEY']}"},
json={},
)
print(r.json()) Appears in
Change history
How this free tier has changed since we started tracking it (2026-07-31) — generated from the git history of providers.json.
- 2026-08-14 Updated card requirement
- 2026-07-31 Added to the hub