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GPT-4o mini TTS (2025-12-15)

openai/gpt-4o-mini-tts-2025-12-15Retires Jan 6, 2027

December 2025 snapshot of GPT-4o mini TTS that OpenAI says cut word error rate by about 35% versus the previous generation on Common Voice and FLEURS. Deprecated on 2026-10-01 with removal on 2027-01-06; OpenAI suggests gpt-realtime-2.1-mini instead.

API
curl "$AUDIOLAB_API_URL/v1/audio/speech" \
  -H "Authorization: Bearer $AUDIOLAB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "openai/gpt-4o-mini-tts-2025-12-15",
  "input": "Make every word count.",
  "voice": "auto",
  "response_format": "mp3"
}' --output speech.mp3
Input Price
$12.75 / 1M characters
Output Price
—
Input
Text
Output
Audio

Capabilities

Explore what GPT-4o mini TTS (2025-12-15) supports, then use the API section for a request tailored to this model.

BatchStreamVoicesInstructionsPricing estimated

Languages

Multilingual

Model Information

Provider
OpenAI
Product
Text-to-Speech
Release Date
Dec 15, 2025
Data Policy
No training
Region
Global
Input
Text
Output
Audio
Provider Documentation

Playground

Try GPT-4o mini TTS (2025-12-15) by OpenAI. Requests use the selected workspace’s credits and API pricing.

GPT-4o mini TTS (2025-12-15)Credits —
GPT-4o mini TTS (2025-12-15)
⌘ / Ctrl + Enter to send

Providers

Compare available endpoints, pricing, and context limits for GPT-4o mini TTS (2025-12-15).

ProviderContextOutputInput PriceOutput PriceEndpoint
OpenAINot specifiedAudio$12.75 / 1M characters—
openai/gpt-4o-mini-tts-2025-12-15:openai

Prices are catalog rates. Your workspace’s estimate and endpoint pricing determine the final charge.

Input and Output Limits

Formats and limits AudioLab enforces on each request.

LimitValue
Max chars4096
Formatsmp3, opus, aac, flac, wav, pcm

Provider Notes

All current models support MP3, Opus, AAC, FLAC, WAV, and raw PCM at speeds from 0.25 to 4. gpt-4o-mini-tts and its pinned snapshot accept delivery instructions, all 13 current built-in voices, eligible custom voice IDs, and stream_format=audio or sse. Legacy tts-1 and tts-1-hd reject instructions, custom voices, SSE event framing, and the newer cedar, marin, verse, and ballad voices. OpenAI requires end users to be told that the voice is AI-generated.

Performance

Status

Current catalog availability. Your workspace’s access is checked separately before a request runs.

Getting Started

Use your workspace API key and the exact model identifier below. Set the API URL to the endpoint shown in your workspace and keep credentials on your server.

API
curl "$AUDIOLAB_API_URL/v1/audio/speech" \
  -H "Authorization: Bearer $AUDIOLAB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "openai/gpt-4o-mini-tts-2025-12-15",
  "input": "Make every word count.",
  "voice": "auto",
  "response_format": "mp3"
}' --output speech.mp3
Read the Endpoint Reference

Request Parameters

Available parameters depend on the provider and request format. The endpoint reference explains accepted values and required fields.

ParameterDetails
modelopenai/gpt-4o-mini-tts-2025-12-15 — Required model identifier.
stream_formatView Accepted Values

Input and Output Limits

Formats and limits AudioLab enforces on each request.

LimitValue
Max chars4096
Formatsmp3, opus, aac, flac, wav, pcm

Similar Models

Explore more text-to-speech and compare their capabilities.

ModelContextInput PriceOutput Price
GPT-4o mini TTSOpenAINot specified$12.75 / 1M characters—
TTS-1OpenAINot specified$12.75 / 1M characters—
TTS-1 HDOpenAINot specified$25.50 / 1M characters—
Sonic 3.6CartesiaNot specified$38.25 / 1M characters—
Sonic 3.6 (2026-08-27)CartesiaNot specified$38.25 / 1M characters—
tts-rt-v2SonioxNot specified$11.985 / 1M characters—
View All Text-to-Speech