kokoro-js

High-quality text-to-speech for the web with Apache-2.0 license.

GrowingOpen SourceLow lock-in

Pricing

Free tier

Flat rate

Adoption

Cooling

License

Open Source

Data freshness

Aging · Jun 8, 2026

Overview

What is kokoro-js?

Kokoro.js is a high-quality text-to-speech library designed specifically for web applications, offering developers an easy way to integrate speech synthesis capabilities into their projects under the permissive Apache-2.0 license.

Key differentiator

Kokoro.js stands out as an open-source, high-quality text-to-speech library specifically tailored for web applications, offering developers a free and easy way to integrate speech synthesis capabilities.

Capability profile

Capability Radar

Ease of StartEcosystemValueMaturityFlexibilityScale Ready

Honest assessment

Strengths & Weaknesses

↑ Strengths

High-quality speech synthesis for web applicationsmedium

Open-source under Apache-2.0 licensemedium

Easy integration into web projectsmedium

↓ Weaknesses

Limited language supporthigh

Kokoro.js primarily supports English and lacks robust support for other languages, limiting its global applicability.

Performance issues with complex text inputsmedium

The library can struggle with long or complex sentences, leading to slower synthesis times and sometimes less natural speech output.

Sparse community support and documentationhigh

The official documentation is minimal, and the community around Kokoro.js is small, making it difficult for developers to find help or resources.

Dependency on specific web browser featuresmedium

Kokoro.js relies heavily on Web Audio API which may not be fully supported in all browsers, leading to inconsistent performance across different platforms.

Fit analysis

Who is it for?

✓ Best for

Web developers looking for a high-quality text-to-speech solution under an open-source license

Projects requiring easy integration of speech synthesis capabilities into web applications

✕ Not a fit for

Applications needing real-time voice processing or complex voice interactions beyond basic TTS

Teams that require cloud-hosted services rather than local integrations

Cost structure

Pricing

Free Tier

Available

Open source — free to use

Starts at

$0

Model

Flat rate

Enterprise

None

Performance benchmarks

How Fast Is It?

Ecosystem

Relationships

Next step

Get Started with kokoro-js

Step-by-step setup guide with code examples and common gotchas.

View Setup Guide →