Overview
Synthesises natural-sounding audio from text. Designed for IVR, conversational agents and short narration. Served on GPU: a short sentence takes about 0.2 s end to end through the API, fit for real-time use.
Endpoint and model
POST https://api.tesseraai.cloud/v1/audio/speech. model: kokoro-82m. voice: see catalogue below.
| Attribute | Value |
|---|---|
| Upstream model | hexgrad/Kokoro-82M |
| P50 latency | <200 ms for phrases under 30 chars |
| Output formats | mp3 (default), wav, opus, aac, flac, pcm |
| Sample rate | 24 kHz mono |
| Licence | Apache 2.0 |
Available voices
Each voice encodes language + gender in its prefix: e* Spanish, a* American English, b* British English, p* Brazilian Portuguese, f* French, i* Italian, j* Japanese, z* Mandarin, h* Hindi. The second letter is f (female) or m (male).
| Language | Voices |
|---|---|
| Spanish (neutral, ES + LATAM) | ef_dora, em_alex, em_santa |
| American English | af_heart, af_sky, af_bella, af_nicole, af_sarah, af_aoede, af_kore, af_jessica, af_nova, af_river, af_jadzia, am_michael, am_adam, am_eric, am_fenrir, am_liam, am_onyx, am_puck, am_santa |
| British English | bf_alice, bf_emma, bf_isabella, bf_lily, bm_daniel, bm_fable, bm_george, bm_lewis |
| Brazilian Portuguese | pf_dora, pm_alex, pm_santa |
| French | ff_siwis |
| Italian | if_sara, im_nicola |
| Japanese | jf_alpha, jf_gongitsune, jf_nezumi, jf_tebukuro, jm_kumo |
| Mandarin | zf_xiaobei, zf_xiaoni, zf_xiaoxiao, zf_xiaoyi, zm_yunjian, zm_yunxi, zm_yunxia, zm_yunyang |
| Hindi | hf_alpha, hf_beta, hm_omega, hm_psi |
Hit Play to hear any voice
54 voices, 9 languages. Filter by language and gender; copy the ID to your clipboard to drop straight into your request.
Language
Gender
Request
POST /v1/audio/speech
curl https://api.tesseraai.cloud/v1/audio/speech \
-H "Authorization: Bearer $TESSERA_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "kokoro-82m",
"input": "Welcome to Tessera. Your request has been received.",
"voice": "af_heart",
"response_format": "mp3"
}' \
--output welcome.mp3Response
The response body is raw audio in the requested format. No JSON wrapper.