About this model or application
Fish Audio provides hosted S2.1 speech and separately licensed S2 Pro weights.
Family & other versions4 sources
Background for the family or other versions. These sources are counted separately from evidence for this release.
Family & other versions
Production and free S2.1 tiers plus the exact Transcribe Pro header.
Family & other versions
UTF-8 byte TTS pricing, audio-hour ASR pricing and shared concurrency.
Family & other versions
Official S2 Pro weights, dual-AR architecture and commercial-use restriction.
Family & other versions
Research-weight license; commercial use needs separate permission.
Model family catalog3
Current models
Official catalogFish Audio S2.1 ProAvailableAPI
- Model ID
s2.1-pro- Released
- Not stated
- Availability
- Available
- Input
- Text · Audio
- Output
- Audio
- Deployment / access
- API
- Capabilities
- Speech generation · Multilingual
First-party endpoint pricing
83 languages; production tier with TTFA and DPA guarantees. Reference audio supports voice selection and cloning.
Fish Audio S2.1 Pro FreeRestrictedAPI
- Model ID
s2.1-pro-free- Released
- Not stated
- Availability
- Restricted
- Input
- Text · Audio
- Output
- Audio
- Deployment / access
- API
- Capabilities
- Speech generation · Multilingual
First-party endpoint pricing
USD / million bytes- Input
- 0
Development/testing free tier; subject to fair-use limits, without TTFA or DPA guarantees.
Same S2.1 model, separate access tier rather than another foundational version.
Fish Audio S2 ProAvailableOpen weightsAPI
- Model ID
fishaudio/s2-pro- Released
- Not stated
- Availability
- Available
- Input
- Text · Audio
- Output
- Audio
- Deployment / access
- API · Open weights · Local
- Weights
- Open weights
- License
- Fish Audio Research License
- Capabilities
- Speech generation · Multilingual · Fine-tuning
First-party endpoint pricing
Research/noncommercial use is free; commercial weights use needs a separate Fish Audio license. Model card describes 4B slow-AR plus 400M fast-AR; total parameters are not equated to 4B.