★ 5.3k
August 2026
GPL-3.0
Voice & audio
What we checked ourselves
Not copied from the project's own blurb. These are things we opened and verified, with the date.
- 23 Aug 2026We checked that the link to the project still resolves.
- 30 Aug 2026We read the project's own documentation and found no sign that development has stopped.
Where this sits among the 119 tools we list in Voice & audio
- No API key required114 of 119
- Keeps your data on your own machine30 of 119
- Commercial use confirmed as allowed56 of 119
- Requires terminal commands93 that do not →
Only 24 of the 119 meet all of the conditions above.
Counted from our own checks: every tool we list is examined against the same criteria.
What it does
Natural-sounding voices on modest hardware, even a Raspberry Pi. Great for read-aloud and home projects.
Summary based on the project's own description. The Japanese page has a fuller beginner guide: setup difficulty, what to prepare, and a step-by-step start.
Screenshots & visuals
Before you start
- Setup difficultyEasy to start
- Command lineRequired
- API keyNot required
- Sends data onlineNo
Judged automatically from the project's own metadata. Always confirm on the official page.
Piper FAQ
- Is Piper free?
- Yes. It runs on your own machine, so there is no usage-based cost either.
- Do I need to install anything or write code to use Piper?
- It needs the command line. If you are not comfortable typing commands, expect to get stuck during setup.
- Does Piper work on a phone?
- No. It needs a computer.
- Can I use Piper commercially?
- The licence is GPL-3.0. Using it commercially is fine, but if you distribute something built on it you may be required to release that under the same licence. Keep it internal, or check before distributing.
How it compares
The conditions that decide whether you can actually use it, side by side.
| Tool | Command line | API key | Sends data out | Phone | Commercial use |
|---|---|---|---|---|---|
| Piper (this page) | Required | Not needed | No | No | Yes |
| whisper.cpp | Required | Not needed | No | No | Yes |
| supertonic-3 | Required | Not needed | Yes | No | With conditions |
| voicebox | Not needed | Not needed | No | No | Yes |
"Sends data out" means your input is uploaded to someone's server. Pick "No" when the material cannot leave your organisation.