Vosk
Open-source offline speech recognition toolkit for developers in 20+ languages
Own Vosk? Claim it, free to correct the facts and get the verified badge.
Pricing
Free
API
Yes
Open source
Yes
Company
Alpha Cephei
Platforms
What is Vosk?
Vosk is an offline speech recognition toolkit from Alpha Cephei. It turns speech into text on the device itself, with no cloud connection needed, and runs on hardware as small as a Raspberry Pi or a phone.
The toolkit has a streaming API for real-time recognition, can identify speakers as well as transcribe them, and lets you change the vocabulary quickly to improve accuracy. Each language model is about 50 MB, and larger server models are available too. More than 20 languages and dialects are supported, including English, German, French, Spanish, Chinese, Russian, Japanese, Hindi and Arabic. You can install it with pip, and there are bindings for Java, C#, JavaScript and other languages.
Vosk is published on GitHub under the Apache-2.0 license. It suits developers who build voice features into apps, embedded devices or servers and need recognition to stay private and offline.
Key features
- Fully offline speech recognition
- Streaming API for real-time transcription
- Speaker identification
- Quick vocabulary reconfiguration
- Compact models of about 50 MB per language
- Larger server models available
- Bindings for Python, Java, C#, JavaScript and more
- Runs on Raspberry Pi, Android and iOS
Use cases
Who it's for
Voice control on embedded devices
Add speech commands to Raspberry Pi or other small devices that work without an internet connection.
Private transcription
Transcribe audio on your own servers so recordings never go to a third-party cloud.
Mobile voice input
Build offline speech recognition into Android and iOS apps using the compact models.
Real-time captioning
Use the streaming API to turn live audio into text as it is spoken.
Vosk pricing
From the vendor's site, checked Oct 26, 2026; we re-check prices monthly. Prices change — confirm on their pricing page.
Open source
forever
Free
- Apache-2.0 license
- Offline speech recognition
- Models for 20+ languages
How Vosk compares
- Vosk has a free plan, like 3 of the 4 alternatives below.
- It is open source, as is 1 other.
| Tool | Starts at | Free plan | Free trial | API | Open source | |
|---|---|---|---|---|---|---|
| V | Free | — | ||||
O OpenWhispr | $6.67/mo | — | Vosk vs OpenWhispr | |||
W Wispr Flow | $12/mo | — | — | — | Vosk vs Wispr Flow | |
A Amazon Transcribe | — | — | Vosk vs Amazon Transcribe | |||
R Reduct | $12/mo | — | — | Vosk vs Reduct |
Compare 7 capabilities
| Capability | Vosk | OpenWhispr | Wispr Flow | Amazon Transcribe | Reduct |
|---|---|---|---|---|---|
| Speaker labels | — | ||||
| Bot-free recording | — | — | — | ||
| File upload | — | — | |||
| Mobile app capture | — | — | — | — | |
| Custom note templates | — | — | — | — | |
| HIPAA compliant | — | — | |||
| MCP server | — | — | — |
Capabilities as stated on each vendor's own site; — means the site doesn't say. The closest alternatives in our directory by category. “Starts at” is the cheapest paid plan per month, as each vendor lists it.
Pros and cons
Strengths
- Open source under the Apache-2.0 license
- Works fully offline, including on lightweight devices
- Supports 20+ languages and dialects
- Small models of about 50 MB each
Limitations
- A developer toolkit, with no ready-made end-user app
- No commercial plans or pricing published on the site
Vosk FAQ
Is Vosk free?
Yes. Vosk is open source and published on GitHub under the Apache-2.0 license. The site does not publish any paid plans.
Does Vosk need an internet connection?
No. It runs offline, even on lightweight devices such as a Raspberry Pi.
Which platforms and languages does it support?
The site lists Raspberry Pi, Android and iOS, plus servers. There are bindings for Python, Java, C#, JavaScript and others, and models for 20+ spoken languages.
How do I get support?
Through GitHub issues, by email at contact@alphacephei.com, or in the Telegram, Discord, Matrix and Reddit communities.
User reviews
No reviews yet. Used Vosk? Be the first.
Sign in to rate this tool and share how you use it.
Vosk in our articles
Vosk
Free
Tools similar to Vosk
Open-source voice dictation and bot-free meeting notes with on-device models
Voice dictation that turns speech into clean, formatted text in any app
Managed speech-to-text service on AWS for batch and streaming audio