Text to speech (TTS) API: natural English speech with 28 voices (American and British, female and male; Kokoro-82M, open-licensed). Returns MP3 or WAV. Default voice af_heart; list voices at GET /v1/voices. Runs at about real time: 1,000 characters take about a minute. Priced per character.
https://api.language123.net/v1/tts