Neuphonic API
UK voice company focused on on-device and on-prem TTS (NeuTTS open models that run on CPU) with a hosted SSE/WebSocket API in 37 languages. API pricing is not published.
Overview
Best for: Teams that want the same voices hosted and on-device/on-prem (CPU) for privacy.
At a glance
Sub-25 ms is a vendor figure cited by third parties; an independent benchmark measured ~763 ms. 37 languages per homepage, model spec lists 7. Pricing quote-based. Open weights are the NeuTTS Air/Nano models. Also SSE.
Text with inline <pause> and <phoneme> tags
Not verified
37 (homepage playground); NeuTTS-2M spec lists 7
Instant voice cloning
Third-party listings cite a vendor sub-25 ms figure; Vapi Humanness Index measured ~763 ms for the model it tested.
Not specified
Not verified.
Features
- SSE and WebSocket streaming
- voice cloning
- phoneme-level pronunciation tags
- on-device and on-prem deployment
Pricing
| What | Price | Unit |
|---|---|---|
| API | Not published |
Pricing not published
Free tier: Playground available; API free tier not verified
Source: neuphonic.com
Setup
- Get an API key from app.neuphonic.com.
- pip install pyneuphonic (Python) or @neuphonic/neuphonic-js.
- Use the SSE client for one-shot streaming or the WebSocket client for multi-chunk input.
Endpoint
See docs.neuphonic.comAuthentication
API key
Warnings
No public price list
API pricing is quote-based; budget cannot be estimated from public pages.
Latency claims vary wildly
A vendor sub-25 ms figure circulates while an independent benchmark measured ~763 ms; test before choosing for live agents.
Language counts disagree
Homepage says 37 languages; model spec lists 7 and directories list 7-10.
Plus 12 warnings that apply to all text-to-speech, streaming APIs. See category warnings.
Limits
- Cloning samples: MP3/WAV, min 6 s, under 10 MB (third-party)
Models and products
| Name | Status |
|---|---|
| NeuTTS-2M / NeuTTS-2E | Listed on site |
| neutts-air / neutts-nano (open weights) | Open weights |
Docs and sources
Docs
Sources used
- neuphonic.com/
- docs.neuphonic.com/
- humannessindex.vapi.ai/providers/neuphonic
- docs.pipecat.ai/api-reference/server/services/tts/neuphonic
Pricing, output formats, exact endpoints, latency.