OpenAI API
- Free tier
- No
- Limits tracked
- 0
- Last checked
- Last change
- None recorded
About OpenAI API
Tell it how to speak in plain words, like “whisper” or “hurry”. API only.
OpenAI’s text-to-speech works by picking a built-in voice and describing the delivery in ordinary sentences. With gpt-4o-mini-tts, tone, emotion, intonation, accent, speed and whispering can all be set through written instructions. It is used through the audio/speech API, returns MP3, WAV and other formats, and supports streaming playback, so it suits developers already on the OpenAI API. When you publish the audio, listeners must be told it is AI-generated.
Characteristics
- gpt-4o-mini-tts takes written instructions for tone, emotion, intonation, accent, speed and whispering
- Built-in voices; the older tts-1 and tts-1-hd models are still available
- Output as MP3, Opus, AAC, FLAC, WAV or PCM, with streaming playback
- Custom voices from a consented recording of the speaker, by approval
Summarized by TierDiff from the vendor's own documentation, checked on Oct 16, 2026. Sources: OpenAI API docs — Text to speech, OpenAI API docs — gpt-4o-mini-tts
What the free tier includes
No free-tier limits are recorded for this service.
OpenAI API next to other AI APIs
The same limits for 7 services in this category. OpenAI API is the highlighted row.
| Service | Requests per day | Requests per minute | Tokens per day | Tokens per minute | Source |
|---|---|---|---|---|---|
| OpenAI API Speech API you steer with written instructions such as "whisper" or "speak quickly". This page No free tier | not published | not published | not published | not published | developers.openai.comchecked Oct 23 |
| Anthropic API Trial only | not published | not published | not published | not published | platform.claude.comchecked Oct 23 |
| Google Gemini API | not published | not published | not published | not published | ai.google.devchecked Oct 23 |
| Groq | 1,000 | 30 | 200K | 8,000 | console.groq.comchecked Oct 23 |
| OpenRouter | not published | not published | not published | not published | openrouter.aichecked Oct 23 |
| Replicate No free tier | not published | not published | not published | not published | replicate.comchecked Oct 23 |
| Together AI No free tier | not published | not published | not published | not published | together.aichecked Oct 22 |
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