AI Text-to-Speech (Supertonic TTS 2)

Free AI Text to Speech with Supertonic TTS 2 - Multilingual Browser TTS

What is Supertonic TTS 2 and how does it work?

Supertonic TTS 2 is a diffusion-based text-to-speech model developed by Supertone. This tool runs the ONNX-converted version entirely in your browser via Transformers.js - no data leaves your device. The model uses a multi-step denoising process to generate high-quality 44.1kHz audio from text, with controllable speaking speed and 10 distinct voice options across male and female speakers.

Which languages does Supertonic TTS 2 support?

Supertonic TTS 2 supports five languages: English (en), Korean (ko), Spanish (es), Portuguese (pt), and French (fr). You can select the language from the dropdown and type text in the corresponding language. Each language works with all 10 available voices.

What voices are available in Supertonic TTS 2?

The model includes 10 speaker voices: five female (F1-F5) and five male (M1-M5). Each voice has a distinct character and tone. You can preview them by generating a short test sentence with each voice to find the one that suits your content.

Can I control the speaking speed?

Yes. Supertonic TTS 2 supports adjustable speaking speed from 0.5x to 2.0x. The default speed of 1.0x produces natural-paced speech. Lower values slow the speech down for clarity, while higher values speed it up for faster delivery.

How does Supertonic TTS 2 compare to KittenTTS?

While KittenTTS focuses on English-only speech with a StyleTTS2 architecture, Supertonic TTS 2 offers multilingual support across 5 languages and uses a diffusion-based approach that produces 44.1kHz audio - higher quality than the 24kHz output of KittenTTS. The trade-off is a larger model download (~263MB vs 41-79MB for KittenTTS) and longer generation time due to the iterative denoising process.

Is Supertonic TTS 2 free to use?

Yes, completely free with no sign-up required. The model runs locally in your browser using WebAssembly, so there are no API costs, no usage limits, and no account needed. Your device's processing power determines generation speed.

Is my text data private?

Absolutely. All inference happens locally in your browser. Your text is never uploaded to any server. The model weights are downloaded once from Hugging Face and cached in your browser for reuse.

What browsers support Supertonic TTS 2?

Supertonic TTS 2 works in any modern browser with WebAssembly support, including Chrome, Edge, Firefox, and Safari. Generation time depends on your device - on a typical laptop, expect a few seconds for a short sentence.

Use cases for multilingual AI text-to-speech

This tool is useful for creating voiceovers in multiple languages, generating pronunciation samples for language learning, producing accessibility audio for international audiences, and prototyping multilingual content. The high-quality 44.1kHz output is suitable for professional use.

Related tools for your audio workflow

Combine this with our AI Audio Transcriber to convert speech back to text, or use the Audio to Video Visualizer to turn your generated audio into a shareable video. For a lighter English-only TTS with faster loading, try KittenTTS Nano.

This is not an official tool by Supertone. Supertonic TTS 2 ONNX is converted and published by the ONNX Community on Hugging Face.