Speech recognition software is available for many computing platforms, operating systems, use models, and software licenses. Here is a listing of such, grouped in various useful ways.
The following list presents notable speech recognition software engines with a brief synopsis of characteristics.
| Application name | Description | Open-source | License | Operating system | Programming language | Supported language, note | Offline or online |
|---|---|---|---|---|---|---|---|
| CMU Sphinx | HMM | Yes | BSD style | Cross-platform | Java | English, German, French, Mandarin, Russian | Offline |
| HTK | HMM neural net | No | HTK specific | Cross-platform | C | English; version 3.5 released December 2015 | |
| Julius | HMM trigrams | Yes | BSD style, non-commercial | Cross-platform | C | Japanese, English; | Offline |
| Kaldi | Neural net | Yes | Apache | Cross-platform | C++ | English | |
| RWTH ASR | RWTH Aachen University | No | RWTH ASR, non-commercial use only | Linux, macOS | C++ | English | |
| Whisper | Encoder/decoder transformer | Yes | MIT license | Cross-platform | Python (programming language) | Multilingual | Online (through API) and Offline |
| Application name | Description | Open-source | License | Price | Note |
|---|---|---|---|---|---|
| Dragon for Mac (discontinued 2018) | macOS; by Nuance | No | Proprietary | ||
| Dragon Dictate (discontinued) | macOS; by Nuance | No | Proprietary | ||
| MacSpeech Scribe (discontinued) | Transcription from recorded text; acquired by Nuance | ||||
| iListen (discontinued) | PowerPC Macintosh; discontinued by MacSpeech; acquired by Nuance | ||||
| Speakable items | Included with macOS | ||||
| ViaVoice (discontinued) | IBM Product; acquired by Nuance | ||||
| Voice Navigator | Original GUI voice control; 1989 | ||||
| Weesper Neon Flow | Voice-dictation software for macOS 11+; 100% offline processing; cross-app dictation | No | Proprietary | €5/month (free trial) | Provides local speech-to-text on device; available for macOS and Windows [1] |
The following list presents notable speech recognition software that operate in a Chrome browser as web apps. They make use of HTML5 Web-Speech-API. [2]
| Application name | Description | Open-source | License | Price | Note |
|---|---|---|---|---|---|
| Speechmatics [3] | Cloud based and on-premise automatic speech recognition | No | Proprietary | From £0.06 per minute of audio |
Many mobile phone handsets, including feature phones and smartphones such as iPhones and BlackBerrys, have basic dial-by-voice features built in. Many third-party apps have implemented natural-language speech recognition support, including:
| Application name | Description | Open-source | License | Price | Note |
|---|---|---|---|---|---|
| Assistant.ai | Assistant for Android, iOS and Windows Phone | No | Proprietary, freeware | Free | Discontinued |
| Dragon Dictation | No | Proprietary, freeware | Free | ||
| Google Now | Android voice search | No | Proprietary, freeware | Free | |
| Google Voice Search | No | Proprietary, freeware | Free | ||
| Microsoft Cortana | Microsoft voice search | No | Proprietary, freeware | Free | |
| Siri Personal Assistant | Apple's virtual personal assistant | No | Proprietary, freeware | Free | |
| Alexa – Amazon Echo | Amazon's personal assistant | No | Proprietary | ||
| SILVIA | Android and iOS | No | |||
| Vlingo |
The Windows Speech Recognition version 8.0 by Microsoft comes built into Windows Vista, Windows 7, Windows 8 and Windows 10. Speech Recognition is available only in English, French, Spanish, German, Japanese, Simplified Chinese, and Traditional Chinese and only in the corresponding version of Windows; meaning you cannot use the speech recognition engine in one language if you use a version of Windows in another language. Windows 7 Ultimate and Windows 8 Pro allow you to change the system language, and therefore change which speech engine is available. Windows Speech Recognition evolved into Cortana (software), a personal assistant included in Windows 10.
The first version of the Microsoft Speech API was released for Windows NT 3.51 and Windows 95 in 1995, it was then part of Windows up to Windows Vista. This initial version already contained Direct Speech Recognition and Direct Text To Speech APIs which applications could use to directly control engines, as well as simplified 'higher-level' Voice Command and Voice Talk APIs. Speech recognition functionality included as part of Microsoft Office and on Tablet PCs running Microsoft Windows XP Tablet PC Edition. It can also be downloaded as part of the Speech SDK 5.1 for Windows applications, but since that is aimed at developers building speech applications, the pure SDK form lacks any user interface (numerous applications were available), and thus is unsuitable for end users.
The following are interactive voice response (IVR) systems: