MAI-Voice-2.1

Overview

MAI-Voice-2.1 is Microsoft AI's highest-fidelity, most expressive text-to-speech model. It produces natural, studio-grade speech across 23 languages, with detailed prosody, nuanced expressiveness, and speaker consistency over long-form content. Pick a voice by its locale-prefixed ID.

Usage

All media models use the async job queue. Submit a job, then poll for the result.

Step 1: Submit Job

const res = await fetch('https://api.yepapi.com/v1/media/queue', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    model: 'microsoft/mai-voice-2.1',
    prompt: 'Your text to speak goes here.',
    options: { voice: 'en-US-Harper:MAI-Voice-2.1' },
  }),
});
const { data } = await res.json();
// data.jobId — use this to poll for results

curl -X POST https://api.yepapi.com/v1/media/queue \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "microsoft/mai-voice-2.1", "prompt": "Your text to speak goes here."}'

Step 2: Poll for Result

const status = await fetch(`https://api.yepapi.com/v1/media/status/${data.jobId}`, {
  headers: { 'x-api-key': 'YOUR_API_KEY' },
});
const { data: job } = await status.json();
// job.status — "pending" | "processing" | "completed" | "failed"
// job.result.audio — { mimeType, base64 } when completed

curl https://api.yepapi.com/v1/media/status/JOB_ID \
  -H "x-api-key: YOUR_API_KEY"

Write the audio to a file:

import { writeFileSync } from 'node:fs';

writeFileSync('speech.mp3', Buffer.from(job.result.audio.base64, 'base64'));

Request Body

Voices

en-US-Harper:MAI-Voice-2.1 is used when options.voice is omitted. 97 voices available (10 of 97 shown):

• en-US-Harper:MAI-Voice-2.1
• en-GB-Emily:MAI-Voice-2.1
• es-MX-Valeria:MAI-Voice-2.1
• fr-FR-Soleil:MAI-Voice-2.1
• de-DE-Klaus:MAI-Voice-2.1
• it-IT-Rosa:MAI-Voice-2.1
• pt-BR-Luana:MAI-Voice-2.1
• hi-IN-Priya:MAI-Voice-2.1
• ko-KR-Haena:MAI-Voice-2.1
• zh-CN-Mei:MAI-Voice-2.1

Features

• Microsoft AI's highest-fidelity, most expressive TTS model
• 23 languages, 97 voices across 28 locales
• Detailed prosody and nuanced expressiveness
• Speaker consistency over long-form content

Billing

Speech is billed on the length of the input text, in UTF-8 bytes — for English text one byte is one character. The cost is known before synthesis starts, so the balance check at submit time quotes the exact final charge. Jobs have a $0.01 minimum.