Piper vs KittenTTS Nano
Two open-source models that run fully in your browser — compared on the numbers that matter, with both available to try free so you can hear the difference on your own text.
| Piper | KittenTTS Nano | |
|---|---|---|
| Parameters | 20M | 15M |
| Download | 27-115 MB per voice | 57 MB |
| Quality rank (of our lineup) | #5 | #6 |
| Speed | ≈ 9× faster than real-time on CPU — no GPU needed at all. | Faster than real-time on virtually any device, including old phones. |
| Voices | 900 | 8 |
| Languages | 24 | 1 |
| Voice cloning | No | No |
| Streaming | No | No |
| Hardware | Any CPU (WASM) | Any CPU (WASM) |
| License | MIT (core) | Apache-2.0 |
| Output | 22.1 kHz | 24.0 kHz |
Which should you choose?
- Piper if you want the most natural output and your device meets its requirements (≈ 9× faster than real-time on CPU — no GPU needed at all.).
- KittenTTS Nano if download size or low-end hardware matters — it needs 57 MB and runs on any CPU.
- Piper if you need languages beyond English (24 supported vs 1).
Frequently asked questions
Which sounds better, Piper or KittenTTS Nano?
Piper ranks higher for naturalness in our lineup. But "better" depends on the job — KittenTTS Nano wins when download size or low-end hardware matters — it needs 57 MB and runs on any CPU. Generate the same sentence with each and let your ears decide.
Are these comparisons measured or copied?
Speed and size figures come from the models' published specs and our own in-browser runs; the benchmark page lets you reproduce every number on your own hardware.