# Vosk Review

> Vosk review: Lightweight offline STT toolkit for edge and embedded devices. Verified pricing, features, and the strongest alternatives in Speech-to-text APIs.

![Vosk logo](https://www.versusref.com/logos/vosk.png)

Lightweight offline STT toolkit for edge and embedded devices

Among the 43 speech-to-text tools we track, Vosk has the 34th-widest language coverage.

See pricing · Open source · facts verified Jul 20, 2026

## What we know about Vosk

This is our verified profile of Vosk, a speech-to-text apis platform - lightweight offline STT toolkit for edge and embedded devices. Every fact about Vosk below carries the source it came from and the day we checked it.

Vosk does not publish a public per-minute rate we have been able to verify, so the price figure here stays blank until we can confirm one. We would rather show nothing than a guessed number; if you have a current Vosk quote, it is the fastest way for us to close that gap.

On capabilities, Vosk covers word-level timestamps, custom vocabulary / keyterm boosting, self-host / on-prem option, and websocket streaming api. Each of those is verified against Vosk's own docs or dashboard, not marketing copy.

Vosk ranks the 34th-widest language coverage of the 43 speech-to-text tools we track, so where it lands for you depends on which of those matters more.

In total we track 12 verified facts for Vosk today, each linking the primary source it came from so you can check our work - and vendor claims we have not measured ourselves are labeled as such on the Vosk fact sheet below.

## Fact sheet

### Capabilities

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| WER (vendor-claimed) | ~5.69 % WER | Jul 20 | [source](https://alphacephei.com/vosk/models) |
| Languages supported | 20 languages | Jul 20 | [source](https://alphacephei.com/vosk/) |
| Word-level timestamps | ✓  Yes | Jul 20 | [source](https://github.com/alphacep/vosk-api/blob/master/src/vosk_api.h) |
| Custom vocabulary / keyterm boosting | ✓  Yes | Jul 20 | [source](https://alphacephei.com/vosk/adaptation) |

### Compliance & trust

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Self-host / on-prem option | ✓  Yes | Jul 20 | [source](https://alphacephei.com/vosk/) |
| Model weights license | Apache-2.0 | Jul 20 | [source](https://alphacephei.com/vosk/models) |

### Build experience

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Official SDKs | Python, Java, Node.js, C#, C++, Rust, Go | Jul 20 | [source](https://github.com/alphacep/vosk-api) |
| Websocket streaming API | ✓  Yes | Jul 20 | [source](https://alphacephei.com/vosk/server) |

### Commercial

| Fact | Value | Verified | Source |
| --- | --- | --- | --- |
| Model size (parameters) | Small models ~50MB; large server models 1-2GB | Jul 20 | [source](https://alphacephei.com/vosk/models) |
| Hardware to self-host | Runs on Raspberry Pi, Android, iOS | Jul 20 | [source](https://alphacephei.com/vosk/) |
| Project maintenance status | Active - commits 2026-07; last release v0.3.50 (2024-04) | Jul 20 | [source](https://github.com/alphacep/vosk-api) |
| GitHub stars | 14,964 stars | Jul 20 | [source](https://github.com/alphacep/vosk-api) |

Source: https://www.versusref.com/stt/tools/vosk/