Audience
Developers and product teams building mobile, desktop, web, embedded, or server applications that need text-to-speech, including offline or privacy-sensitive use cases.
About Phonon
Phonon is an open-weight text-to-speech (TTS) model and inference runtime for developers adding speech generation to applications that need local, offline audio. It converts text into spoken audio and can stream speech as it is generated. The runtime provides Rust and Python interfaces, a Swift package for iOS and macOS, JavaScript for browsers, and Android libraries; it can also run as a self-hosted server with an OpenAI-compatible API. Depending on the model variant, it supports English, French, German, Spanish, and Portuguese. Phonon is intended for developers integrating speech into mobile, desktop, web, embedded, and server applications, including offline or privacy-sensitive use cases. The 31-million-parameter English model weights use the Apache 2.0 license; 40-million-parameter language-specific and multilingual weights use CC BY-NC 4.0. The runtime code is separately available under Apache 2.0 or MIT.
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Pricing
Free Version:
Free Version available.
Company Information
Gradium
Founded: 2025
France, United States
gradium.ai/phonon
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Product Details
Platforms Supported
Windows
Mac
Linux
iPhone
iPad
Android
On-Premises
Training
Documentation
Phonon Frequently Asked Questions
Q: What kinds of users and organization types does Phonon work with?
Phonon works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Phonon support in their product?
Phonon supports these languages: English, French, German, Spanish, and Portuguese.
Q: What other applications or services does Phonon integrate with?
Phonon integrates with: Hugging Face.
Q: Does Phonon have an API?
Yes, Phonon has an API.
Q: Does Phonon have a mobile app?
Yes, Phonon has a mobile app for Android, iPhone, and iPad.
Q: What type of training does Phonon provide?
Phonon provides training in the form of documentation.
