Fish Audio Voice Cloning API vs Speechify API Voice Cloning

Fish Audio Voice Cloning API

Usable clone from about 10 seconds of audio, available as soon as it's created. No consent or speaker verification in the API.

Speechify API Voice Cloning

Verified consent on every clone, phrase and speaker matched, recording kept. No cloning on the Free plan.

Fish Audio Voice Cloning API

1. Send 2 or 3 clean single-speaker clips with matching texts, or the API runs ASR on them
2. Pass the model _id as reference_id in TTS. Check state before relying on it
3. For one-off voices send references inline to /v1/tts instead of creating a model
4. Send the model: voice-design-1 header on voice design calls
5. Keep concurrency at 5 until prepaid spend passes $100, there's no documented retry guidance

Speechify API Voice Cloning

1. Create the consent challenge only when the speaker is ready. It's single use and short-lived
2. Show the phrase as returned. Rewording it fails the match
3. Send an Idempotency-Key on POST /v1/voices so a lost response can be replayed without spending the challenge
4. Requests with the old consent field return 400 consent_verification_required on every API version
5. On 429 wait for Retry-After, then check error.code to tell a rate limit from a concurrency cap