---
id: "fish-audio/s2.1-pro"
also: ["fish-audio/s2.1-pro-20260729", "vercel/fish-audio/s2.1-pro"]
card_usd_per_m: "15.0 in, 0.0 out, at fish-audio"
cheapest_list_usd_per_m: "15.0 in, 0.0 out, at fish-audio on openrouter"
cheapest_effective_usd_per_m: "15.0 in, 0.0 out, at fish-audio on vercel"
context: 0
max_output: 0
input: ["text"]
output: ["speech"]
released: "2026-07-29"
api: ["/api/v1/audio/speech"]
params: ["max_tokens", "stop", "temperature"]
endpoints: 2
gateways: "openrouter (1), vercel (1)"
no_training: 1
trains: 1
retains_prompts: 1
---
# Fish Audio: S2.1 Pro

S2.1 Pro is Fish Audio's current state-of-the-art voice model — the best model we have, now available to every developer for free via API. It is a neural speech synthesis model designed for production-grade AI voice generation, with particular strengths in low-latency streaming, multilingual TTS, and voice cloning.