Custom Voice Tester πŸŽ›οΈ

66 custom blended voices created by mixing existing Kokoro TTS voice embeddings. Each blend combines 2–5 base voices with different weights to create unique timbres. 20+ Mandarin Chinese recipes are included, plus English, Japanese, European, and fusion blends.

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Load Model

Download Kokoro-82M (~305MB) once. Cached in browser.

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Type Text

Enter test text. English uses local phonemization after assets load; other Kokoro languages use the documented API.

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Test Voices

Click Play on any voice card. Or Play All to hear every voice sequentially.

How custom voice blending works

Each Kokoro TTS voice is stored as a .bin file containing a Float32Array of style embeddings at 256-element intervals. When blending, we take a weighted average of the embedding vectors from multiple source voices, producing a brand-new voice that combines characteristics of all source voices proportionally.

An offline batch process loads source voice .bin files, computes the weighted average, and saves the result as a new .bin file. No retraining or fine-tuning is performed; the result is intended for the compatible Kokoro-82M ONNX model and voice-loading format.

Language handling: The test page detects the dominant source voice's language and uses it for phonemization. For English blends, kokoro-js's built-in espeak phonemizer is used. For non-English blends (Chinese, Japanese, etc.), text is phonemized via the OfflineTTS phonemize API, which runs misaki (Japanese/Chinese) or espeak-ng (other languages). Audio synthesis always happens locally on your device.

API: POST /api/phonemize with { text, lang } β†’ returns IPA phonemes. English codes: a, b. Non-English: j (ja), z (zh), e (es), f (fr), h (hi), i (it), p (pt-br).

What These 66 Blends Represent

Each entry is a precomputed weighted recipe made from two or more existing Kokoro style embeddings. The entries are not 66 separately trained models, verified human identities, licensed celebrity voices, or objective quality winners. Names and trait labels describe the recipe's intended listening direction; they do not guarantee that every sentence will exhibit those traits.

The dominant source prefix selects a language route for phonemization. That is an implementation choice, not evidence that a blend has learned another language or accent. Cross-language and β€œfusion” recipes may be less stable than same-language sources. Count, metadata, and availability are tied to the matching experimental asset bundle rather than the public Kokoro base-voice catalog.

Testing Method and Limitations

Compare blends with one fixed passage, model precision, speed, backend, browser, and device. Include names, numbers, punctuation, questions, and longer clauses, then replay the base voices that contribute the largest weights. Listen for pronunciation, rhythm, intelligibility, loudness, artifacts, and whether the supposed difference remains across more than one sentence.

Play All is a convenience audition, not a blinded benchmark: order, listener fatigue, loudness, and cached results can influence preference. Record the recipe and environment if a comparison will support a public claim. Do not label a blend β€œbest,” assign a numeric quality score, or recommend commercial use without a disclosed corpus, multiple samples, and review of upstream voice and dataset terms.

Noindex Evaluation Route

This route is retained for controlled development and QA and is intentionally excluded from search indexing and the public sitemap. A production build may omit the experimental custom-voice metadata and `.bin` bundle; when those assets are absent, the page cannot list or play the recipes. The base voice library and supported production engines remain available through the main TTS workspace. For any enabled test, speech synthesis is local after assets load, while non-English Kokoro sends test text for phonemization as described in the Privacy Policy. Do not enter confidential text into a workflow whose documented network behavior does not meet your requirements.