Onyx
Grade D Kokoro🇺🇸 American English · ♂ Male Voice
About the Onyx Voice
Onyx is a male American English AI voice rated D on the OfflineTTS quality scale. Speech synthesis runs in your browser with no signup or per-character fees.
Best for: General purpose
How to use the Onyx voice:
- Open the [TTS tool](/app/?voice=am_onyx)
- "Onyx" will be automatically selected in the voice picker
- Type or paste your text (up to 50,000 characters per batch)
- Click generate — speech is created locally on your device
- Download as studio-quality WAV or compact MP3
Quality rating explained: D indicates this voice provides clear, intelligible output suitable for drafts and rapid prototyping.
The Onyx voice uses Kokoro's browser phonemizer and local WebGPU or WebAssembly synthesis. After the initial model download, English generation works completely offline.
Explore other American English voices or browse the [complete voice library](/voice/) for your project.
Best For: General purpose
Onyx is a reliable male American English voice suitable for general voice-over, narration, and content creation.
Generate speech with Onyx now →Related Voices
Onyx Voice — Frequently Asked Questions
Is the Onyx voice free to use?
Yes. The Onyx voice is completely free. It runs in your browser with no API key, no signup, and no subscription limits. Generate as much speech as you need at zero cost.
Does the Onyx voice work offline?
Yes. After the initial model download is cached in your browser, the Onyx voice can generate speech completely offline without internet connectivity.
What quality rating does the Onyx voice have?
The Onyx voice is rated D on our quality scale. This is a solid, clear voice that produces intelligible and natural speech for content creation.
Can I export WAV and MP3 with Onyx?
Yes. After generating speech with Onyx, you can download uncompressed 24kHz WAV files for studio editing or compressed MP3 files for sharing and publishing.
Can I use the Onyx voice for commercial projects?
Yes. The models used on OfflineTTS support commercial content creation. You can use generated audio in YouTube videos, podcasts, audiobooks, and commercial voice-overs.
Ready to use Onyx?
Experience natural American English speech synthesis in your browser with zero setup or character fees.
Open Onyx Voice in TTS Studio →