Text-to-speech

Piper (voices) requirements, license & speed

By Rhasspy / Open Home Foundation · released 2023-06-22

Commercial useConditional
Min memoryNot stated
Runs on CPUYes
StreamingUnknown

Key facts

License
Voices repo: MIT; engine (piper1-gpl): GPL-3.0 source
Commercial use
Conditional source
Engine is GPL-3.0; each voice's training data has its own license, check the voice's MODEL_CARD
Parameters
Unknown
Minimum memory
Not stated by source
Runs on CPU
Yes source
Fast local neural TTS, ONNX on CPU (smoke-tested here)
Streaming
Unknown
Voice cloning
Unknown
Languages
ar, ca, cs, cy, da, de, el, en, es, fa, fi, fr, hu, is, it, ka, kk, lb, lv, ne, nl, no, pl, pt, ro, ru, sk, sl, sr, sv, sw, tr, uk, vi, zh source
Released
2023-06-22 source
Hugging Face repo creation date (proxy for release date)
Gated on HF
No

Measured speed & memory

HardwareRunnerRTFTime to first audioPeak RAMDate
Cloud VM CPU (8 vCPU Intel Xeon, no GPU)piper-tts (onnxruntime) voice=en_US-lessac-medium0.0169 (59× real time) 0.054 s362.0 MB 2026-10-20

Median of 3 runs after warm-up, ~10 s English passage. Peak RAM is whole-process RSS. Methodology

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