Fish AudioAudio matchupSpeech output
Fish Audio S2 Provs.Fish Audio S2.1 Pro
Which model is better?
Fish Audio S2.1 Pro does better in independent tests, while Fish Audio S2 Pro is available with open weights.
Pick Fish Audio S2 Pro for
Pick Fish Audio S2.1 Pro for
Shared tests
Independent evaluators and leaderboards only, the newest shared snapshot per evaluator. With 95 % ranges a lead counts when they do not overlap; for hit rates, when it holds in a 95 % test. Without any uncertainty figure at most “slightly ahead”.
Artificial Analysis
Fish Audio S2.1 Pro aheadFish Audio S2.1 Pro is clearly ahead in 1 of 2 subtests, Fish Audio S2 Pro in none. 1 is level.
Artificial Analysis Provider Voice Arena preference
95 % ranges 1,097 to 1,119 and 1,170 to 1,196, as of November 3, 2026
Artificial Analysis Controlled Voice Arena Elo
95 % ranges 996 to 1,018 and 996 to 1,022, as of November 3, 2026
Source · latest November 3, 2026
VoiceArena
Fish Audio S2.1 Pro aheadFish Audio S2.1 Pro is clearly ahead in 1 of 2 subtests and slightly in 1, Fish Audio S2 Pro in none.
VoiceArena TTS Elo: US English
95 % ranges 929 to 943 and 975 to 1,003, as of October 28, 2026
VoiceArena TTS v1, US English, All, Elo
as of October 17, 2026
Source · latest October 28, 2026
All data side by side
Prices are verbatim from the provider, because audio models bill per minute, character or token.
| Fish Audio S2 Pro | Fish Audio S2.1 Pro | |
|---|---|---|
| Task | Speech output | Speech output |
| Developer | Fish Audio | Fish Audio |
| Status | Open weights | Active |
| Released | March 9, 2026 | June 23, 2026 |
| Weights | open | proprietary |
| Runs locally | yes | no |
| Price | n/a | Free through 2026-11-30 under fair-use rules; changes with advance notice |
| Popularity (out of 100) | 51 | 0 |