Deepgram - Search engine for speech
Jasper - Jasper is an open source platform for developing always-on, voice-controlled applications.
Yack.net - Recorded and transcribed calls for team collaboration
Speechmatics - The most accurate and inclusive speech-to-text API ever released.
Hidden Markov Model Toolkit - Hidden Markov Model Toolkit (HTK) is a portable toolkit used for speech recognition research, speech synthesis, character recognition and DNA sequencing.
LumenVox ASR - LumenVox Automated Speech Recognizer (ASR) is a software solution that converts spoken audio into text, providing users with a more efficient means of input.