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Voice Text to Speech fish

Fish Audio S2.1 Pro

Fish Audio S2.1 Pro costs $0.0090/req on FairStack — a text to speech model for Per-user persistent voice cloning at scale, Products where every customer keeps their own cloned voice. No subscription required. Pay per generation with full REST API access. FairStack applies a transparent 20% margin on infrastructure cost so you always see the real price.

FairStack price
$0.0090/req

What is Fish Audio S2.1 Pro?

Fish Audio S2.1 Pro is the synthesis engine behind FairStack's customer voice cloning. Unlike ElevenLabs (hard-capped at 10 custom voices per account), Fish cloning is cap-free: every user can create and keep their own persistent voice model with no slot wall. Clone a voice from a short reference sample via POST /v1/voice/clone (engine: fish), then generate speech in that voice by passing the returned voice_id to voice generation with this model. Customer-facing generation runs on the free s2.1-pro-free tier at $0 marginal cost. Voice cloning is consent-gated and discloses that voice data is processed by Fish Audio, which may use it to train their models.

Key Features

Cap-free / unlimited persistent voice clones
Clone from a short reference sample (3-15s)
Consent-gated with clear data disclosure
$0 marginal synthesis on the free tier

What are Fish Audio S2.1 Pro's strengths?

No 10-voice slot wall - scales to every user having their own voice
Persistent clones that survive indefinitely (no LRU eviction)
Low/zero marginal cost

What are Fish Audio S2.1 Pro's limitations?

Requires a prior clone (pass the voice_id) - not a standalone catalog voice
Provider may use submitted voice data to train their models (disclosed + consented)

What is Fish Audio S2.1 Pro best for?

Per-user persistent voice cloning at scale Products where every customer keeps their own cloned voice

How much does Fish Audio S2.1 Pro cost?

Metric
FairStack
Details
Price per generation
$0.0090
Includes 20% margin
Per-character rate
$0.000015/char
Min $0.0010/req
Subscription
None
Pay per generation only

How does Fish Audio S2.1 Pro perform across capabilities?

voice clone fidelity
82%
naturalness
83%
multilingual
70%

How do I use the Fish Audio S2.1 Pro API?

curl
curl -X POST https://api.fairstack.ai/v1/generations/voice \
  -H "Authorization: Bearer $FAIRSTACK_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "fish-s2.1-pro",
    "prompt": "Your prompt here"
  }'
Python
import requests

response = requests.post(
    "https://api.fairstack.ai/v1/generations/voice",
    headers={
        "Authorization": f"Bearer {FAIRSTACK_API_KEY}",
        "Content-Type": "application/json",
    },
    json={
        "model": "fish-s2.1-pro",
        "prompt": "Your prompt here",
    },
)

result = response.json()
print(result["url"])
Node.js
const response = await fetch(
  "https://api.fairstack.ai/v1/generations/voice",
  {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.FAIRSTACK_API_KEY}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      model: "fish-s2.1-pro",
      prompt: "Your prompt here",
    }),
  }
);

const result = await response.json();
console.log(result.url);

Frequently Asked Questions

How much does Fish Audio S2.1 Pro cost?

Fish Audio S2.1 Pro costs $0.0090/req on FairStack as of 2026-07-25. This price includes FairStack's transparent 20% margin on infrastructure cost. No subscription or monthly fee — you pay per generation only. Minimum deposit is $1.

What is Fish Audio S2.1 Pro and what is it best for?

Fish Audio S2.1 Pro is the synthesis engine behind FairStack's customer voice cloning. Unlike ElevenLabs (hard-capped at 10 custom voices per account), Fish cloning is cap-free: every user can create and keep their own persistent voice model with no slot wall. Clone a voice from a short reference sample via POST /v1/voice/clone (engine: fish), then generate speech in that voice by passing the returned voice_id to voice generation with this model. Customer-facing generation runs on the free s2.1-pro-free tier at $0 marginal cost. Voice cloning is consent-gated and discloses that voice data is processed by Fish Audio, which may use it to train their models. Fish Audio S2.1 Pro is best for Per-user persistent voice cloning at scale, Products where every customer keeps their own cloned voice. Available via FairStack's REST API with curl, Python, and Node.js SDKs.

Does Fish Audio S2.1 Pro have an API?

Yes. Fish Audio S2.1 Pro is available via FairStack's REST API at api.fairstack.ai. Send a POST request to /v1/generations/voice with your API key and prompt. Works with curl, Python requests, Node.js fetch, and any HTTP client. No SDK installation required.

How does Fish Audio S2.1 Pro compare to other voice models?

Fish Audio S2.1 Pro excels at Per-user persistent voice cloning at scale, Products where every customer keeps their own cloned voice. It is a text to speech model priced at $0.0090/req on FairStack. Key strengths: No 10-voice slot wall - scales to every user having their own voice, Persistent clones that survive indefinitely (no LRU eviction). Compare all voice models at fairstack.ai/models.

Start using Fish Audio S2.1 Pro today

$0.0090/req. Full API access. No subscription.

Start Creating