TensorLocal TTS

Generate natural-sounding speech directly in your browser using on-device AI. No server, no API key — your text stays on your device.

First use requires downloading the voice engine (~87 MB). It will be cached in your browser for instant future use. Works best in Chrome/Edge with WebGPU support.
Voice engine not loaded. Click Load Engine to begin.
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About TensorLocal TTS

TensorLocal TTS is a free, browser-based text-to-speech tool that runs entirely on your device. The voice engine is downloaded once (~87 MB) and cached locally in your browser's IndexedDB. All subsequent uses load instantly from cache with zero network requests — no server, no API key, no usage limits.

How It Works

When you click "Load Engine", the browser downloads the voice engine and initializes the AI inference pipeline. Your text is processed through tokenization, phoneme generation, an acoustic model, and a neural vocoder to produce high-quality 24 kHz WAV audio. If your browser supports WebGPU (Chrome 113+, Edge 113+), inference uses GPU acceleration for faster generation. Otherwise, it falls back to WebAssembly which works on any modern browser.

Available Voices

TensorLocal TTS offers 10 high-quality voice presets across American and British English accents. Each voice has distinct characteristics — from the warm and expressive Heart to the deep and authoritative George. Voice data is downloaded on demand and also cached locally. You can adjust speaking speed from 0.5x to 2.0x without pitch distortion.

Privacy & Performance

Unlike cloud TTS services (Google Cloud TTS, Amazon Polly, ElevenLabs), TensorLocal TTS runs 100% on your device. Your text is never sent to any server. There are no API keys, no usage limits, and no costs. Performance varies by hardware — modern GPUs with WebGPU support can generate a sentence in 1-3 seconds, while CPU-only (WASM) inference may take 5-15 seconds depending on text length and device capability.

Best Practices

  • Use proper punctuation (periods, commas, question marks) for natural prosody and pacing.
  • Keep individual generations under 500 characters for fastest results. Split longer texts into paragraphs.
  • Use Chrome or Edge for WebGPU acceleration — Firefox and Safari will work but may be slower via WASM.
  • The voice engine is cached after first download. Clear your browser's site data if you need to free storage.
  • Currently optimized for English text. Other languages may produce unexpected results.

Use Cases

TensorLocal TTS is ideal for content creators who need voiceover audio for videos and podcasts, educators creating accessible learning materials, developers prototyping voice interfaces, and anyone who needs quick text-to-speech conversion without relying on cloud services. The generated audio is output at 24 kHz sample rate in standard WAV format, compatible with all audio editors and platforms.