IBM Watson Speech to Text vs Vosk
IBM Watson Speech to Text
ibm.comVosk
alphacephei.comSide by side
| Figure | IBM Watson Speech to Text | Vosk |
|---|---|---|
| Price from | $0.02/mo | Free |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| iOS | — | Yes |
| Android | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 5 | 1 |
| Spec score · AI transcription tools | 9.0 (#6) | 8.4 (#15) |
| Spec score · Transcription Software | 8.7 (#11) | 7.9 (#31) |
| Spec score · Speech Recognition Software | 8.7 (#11) | 8.0 (#22) |
| API access | Yes | Yes |
| Export formats | JSON | TXT,SRT |
| Integrations | IBM documents a pre-built phone assistant integration combining watsonx Assistant, Speech to Text, and Watson Text to Speech. | The integrations page lists Asterisk, FreeSWITCH, Jigasi, and UniMRCP integrations. |
| Intended users | IBM identifies customer self-service, agent assistance, and call analytics as use cases, and describes Plus as intended for small businesses and development or testing by larger enterprises. | The FAQ describes Vosk as a practical, plug-and-play speech recognition library for applications, while suggesting Kaldi for research. |
| Speaker identification | Yes | Yes |
| Timestamp support | Yes | Yes |
Plans
IBM Watson Speech to Text
- LitePriced on request
- Plus$0.02 a month
- PlusPriced on request
- LiteFree
- PremiumPriced on request
In their own words
IBM Watson Speech to Text
IBM Watson Speech to Text has no write-up on Specifiction yet; its figures are above.
Vosk
Vosk is an open-source toolkit for speech recognition that works offline, including on devices such as Raspberry Pi, Android, and iOS. It supports more than 20 languages and dialects and includes a streaming API. Developers can reconfigure vocabulary; most small models support dynamic changes. Small models are typically around 50 MB and need about 300 MB of runtime memory, while large server models can require up to 16 GB. Language bindings include Python, Java, C#, and JavaScript, among others. Vosk Server has implementations for WebSocket, gRPC, MQTT, and WebRTC, and listed integrations include Asterisk, FreeSWITCH, Jigasi, and UniMRCP. The server can be installed with Docker and configured to use a locally mounted model folder. Listed systems include Linux x86_64 and arm64, Raspberry Pi 3/4, macOS x86 and M1, and Windows x86 and 64 for the Python package. ARMv6 and Windows ARM64 are unsupported; iOS builds are available on request. The API repository lists an Apache-2.0 license.