Kokoro 82M vs OpenAI gpt-4o-mini-tts
Two text-to-speech models compared on price, context, capabilities and measured speed. External prices are public list rates verified 2026-09-16; Inference APIs prices are live.
| Kokoro 82M | OpenAI gpt-4o-mini-tts | |
|---|---|---|
| Provider | Hexgrad | OpenAI |
| Model id | hexgrad/Kokoro-82M | gpt-4o-mini-tts |
| Price | $5.20 / 1M characters | $12.00 / 1M characters |
| Capabilities | Text to speech, 54 voices, MP3 / WAV, 8 languages | Text to speech, Instructable style |
| Weights | Open | Closed |
| Availability | Available on Inference APIs | Available |
| Rate limits | No daily caps; pay per request | Priced per token by OpenAI; ~$12 per 1M characters equivalent (their estimate ≈ $0.015 per minute of audio). |
| 300 characters → audio | 0.84 s | not measured |
Cost for 1M characters (≈ 11 hours of speech)
Kokoro 82M is about 57% cheaper for this workload at list price. Price is only part of it: free tiers and usage tiers cap how much you can send per day, and a retired model is unavailable at any price. The "Rate limits" row above is the practical difference for a production app.
Measured speed
Speed figures for Inference APIs models are medians of three runs from a European client on 2026-09-16, against the public endpoint, using a ~120-word generation prompt (chat), a 300-character paragraph (speech) or a -second clip (transcription). External models are not measured here; treat "not measured" as unknown, not slow.
When to pick which
- Kokoro 82M — Fast, natural open-weight text-to-speech with 54 voices across 8 languages, on the OpenAI /v1/audio/speech endpoint.
- OpenAI gpt-4o-mini-tts — Priced per token by OpenAI; ~$12 per 1M characters equivalent (their estimate ≈ $0.015 per minute of audio).
Try Kokoro 82M
Same OpenAI request shape; the change is the base URL and key. Full parameters, aliases and pricing on the model page.
External prices and limits come from the linked provider pages and were verified on 2026-09-16. Spotted a change? Tell us.