About SpeakTwin

SpeakTwin is a free tool for practising spoken English with the shadowing technique: you listen to a real speaker one sentence at a time and repeat what they say. See the introduction to shadowing for how it works.

Your data stays on your device

There are no accounts. Your recordings, progress, saved words and settings are stored in your browser on your own device; we never receive them. Clearing your browser data removes them, and you can also delete them from the My practice page.

A few outside services are involved. Videos are played by YouTube’s embedded player, operated by Google. The optional “Check my words” feature uses your browser’s own speech recognition in desktop Chrome and Edge, which may send audio to the browser’s maker; in other browsers it downloads a speech model once (from Hugging Face, with its runtime from jsDelivr) and then runs on your device. The Privacy page explains each of these.

Videos and transcripts

Videos are streamed from YouTube with its own player and remain the property of their creators; each lesson links to the original. Transcripts are shown alongside the video for language study. Where a video is in the public domain or under a Creative Commons licence, the lesson page says so.

When you paste a link to another video, it is played from YouTube in the same way and its subtitles are shown to you alone, for your own practice. Nothing is published.

If you own a video featured here and would like it removed, write to [email protected] and it will be taken down.

Credits

Word meanings, levels and pronunciations come from these open resources:

• CEFR-J Vocabulary Profile 1.5, compiled by Yukio Tono, Tokyo University of Foreign Studies (cefr-j.org), and the Octanove Vocabulary Profile C1/C2 (CC BY-SA 4.0), for word levels.
• Simple English Wiktionary (CC BY-SA), via kaikki.org, for simple definitions.
• WordNet 3.1, Princeton University, for detailed definitions.
• CMU Pronouncing Dictionary, Carnegie Mellon University, for pronunciations.

The word data built from them is shared under the same CC BY-SA 4.0 licence.

Contact

Questions, corrections and suggestions are welcome at [email protected].