Add a sign
Describe a sign in plain language. Our editor turns it into HamNoSys/SiGML notation; a Deaf reviewer validates before it ships.
5–10 minutesOpen-source research project
Text and speech
to sign language.
Kozha converts typed text, recorded speech, or uploaded video into sign language animations. It runs entirely in your browser — no accounts, no servers, no cost.
Add a sign → The dictionary grows when you help.15
Sign languages
On-device
Speech recognition
Free
for educators, always
Input language
Sign language
Tap to record. We'll transcribe and translate.
Upload a video to extract and transcribe audio.
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Features
What Kozha does.
Speech input
Record speech in your browser. Transcription uses your device's built-in speech recognition — no audio leaves your machine.
Text-to-Sign
Type a sentence and see it translated into sign language animations. Words not in the dictionary are fingerspelled automatically.
Video Input
Upload a recorded video. Kozha extracts the audio track, transcribes it, and generates the corresponding sign sequence.
STEM Vocabulary
Pre-loaded with scientific abbreviation packs. "Carbon dioxide" becomes "CO₂" before planning — no manual editing needed.
Automatic Planning
Input text is normalized, lemmatized, and mapped to available signs. The planner reorders words to match sign language grammar.
Deaf-governed Contributions
Every new sign is reviewed by two Deaf native signers before it ships. The Deaf advisory board is currently being seated; until it is, community drafts are queued rather than published. Governance →
The process
How it works.
01
Provide input
Type text, record speech with your microphone, or upload a video file. All three modes work in the same session.
02
Plan the translation
The planner normalizes your text, applies abbreviations, and looks up each token in the sign database. Unknown words are queued for fingerspelling.
03
Animate the signs
The matched signs are rendered as a 3D avatar animation using SiGML data. Everything runs client-side in your browser.
The project lives on contributions
Without contributors,
Without contributors,
this dictionary stays small.
Most sign-language vocabularies on the web cover only a few hundred everyday words. Kozha can only animate what its dictionary contains — so every sign you add unblocks a translation that would otherwise come back blank. This is how the project grows.
Review & refine
Native signers, teachers, and learners — flag awkward translations, fix mistranslations, and help us pick the right regional variant.
A few minutes per signCode or report
Improve the planner, the avatar, or the multilingual pipeline — or just open an issue when something feels off. Every signal helps.
Bug reports welcomeEvery contribution is reviewed by Deaf native signers before it ships. Read the Deaf-led governance →