Speech AI

Complete Speech AI suite — three tools, one API key. Every subscriber receives $10 in free credits to try everything immediately. PRONUNCIATION ASSESSMENT: score English pronunciation at phoneme, word and sentence level (0-100). Returns a score for every word and phoneme, a sentence score, an overall score, the decoded transcript, a confidence value and an audio quality report. Endpoint: POST https://api.brainiall.com/v1/pronunciation/assess/base64 SPEECH-TO-TEXT: convert spoken English to text with word-level timing, per-word confidence and optional speaker labels. Endpoint: POST https://api.brainiall.com/v1/stt/transcribe/base64 TEXT-TO-SPEECH: generate natural speech from text with 54 voices across 9 languages, speed control from 0.5x to 2.0x, and WAV, MP3 or Opus output at 24 kHz. Endpoints: POST https://api.brainiall.com/v1/tts/synthesize and GET https://api.brainiall.com/v1/tts/voices PRICING (Pay As You Go): pronunciation assessment $0.02 per request; speech-to-text $0.01 per request; text-to-speech $0.02 per 1,000 characters; audio transcription $0.02 per minute. Starter plan: $29 per month with 1,500 pronunciation requests included, then the same per-unit pricing. Machine-readable specification: https://api.brainiall.com/api/openapi.json — Keys and usage: https://app.brainiall.com — Built by Brainiall. Speech AI APIs with metered billing.