Coqui TTS

What is Coqui TTS?

Coqui TTS is a comprehensive text-to-speech library that grew out of Mozilla TTS after its lead developer, Josh Meyer, left to found the startup Coqui in 2021. The project bundles training and inference code for a wide range of neural TTS models, so you can synthesize speech, fine-tune models on your own voice, or clone a voice from a short recording.

The flagship model is XTTS, released in late 2023, which clones a voice from as little as six seconds of audio and speaks in 17 languages with zero additional training. That made Coqui TTS the de facto open-source answer to commercial voice cloning services like ElevenLabs.

In April 2024 Coqui announced it was shutting down and handed the project to the community. The repositories remain online, and forks such as the IDIAP-maintained coqui-ai-TTS continue development. For many developers, the project's archive is still the best free toolkit for serious voice synthesis and cloning.

Key Features

• XTTS voice cloning from a short reference audio sample
• Multilingual synthesis in 17 languages
• Training and fine-tuning tools for custom voices
• Support for multiple model architectures in one library
• Runs locally on CPU or GPU, fully offline
• Simple Python API for synthesis and cloning
• Free and open source under MPL-2.0

How to get started

The quickest path is the XTTS demo: install the TTS package with pip, then run the TTS command line tool with a reference audio file and the text you want spoken. Within a minute you will have a cloned-voice audio file. There is also a Gradio demo in the repository that gives you a web interface.

For fine-tuning, the repository includes recipes and scripts, but expect to spend time with data prep and GPU training. Community forums and the active GitHub discussions are the best support channels, since the original company is gone. Check the README for install instructions, since PyTorch setup varies by platform.

• Install the TTS package with pip
• Download or pick a reference voice sample
• Run the TTS command line tool to synthesize speech
• Try the Gradio web demo for cloning experiments
• Explore the training recipes to create custom voices

Use cases

• Adding voice to games, apps and assistants for free
• Voice cloning for accessibility and personalized narration
• Audiobook and e-learning content generation
• Prototyping voice experiences before hiring voice actors
• Research and education in speech synthesis

Pricing and licensing

Coqui TTS is free and open source under the Mozilla Public License 2.0. That license allows commercial use, and modifications to the source files must be made available, but you can build products on top of it without paying licensing fees.

Since the company shut down, there is no official paid support or cloud service. You pay in compute and effort instead: running the larger models locally needs a decent GPU, and maintaining a custom pipeline is on you. The community fork continues to be developed by volunteers.

Pros and cons

Coqui TTS is unmatched in the open-source world for voice cloning quality and multilingual breadth. XTTS clones voices convincingly from tiny samples, everything runs offline, and the MPL license is friendly for commercial projects.

The main risks are maintenance and complexity. The project is effectively in community-maintenance mode, so bugs move slower, and building production-grade TTS from the library takes real engineering. Voice cloning also carries ethical and legal responsibilities, especially for impersonation.

Alternatives

• Piper: lightweight neural TTS that runs on almost any device
• Bark: Suno's open-source text-to-audio with speech, music and effects
• Chatterbox: open-source multilingual TTS with emotional control
• StyleTTS 2: natural-sounding open-source speech synthesis
• ElevenLabs: commercial voice cloning and generation service