Captio AI
🦻 Accessibility + 💻 Productivity App

Czech live captions and productivity tool for lectures

For deaf and hard of hearing people.

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Captio AI app showing live captions

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Use Cases

Every situation covered

Designed for the real moments that matter — not just quiet controlled environments.

🏛️Large lecture halls

Large lecture halls at Charles University Prague, Masaryk University Brno, and Czech Technical University — Czech-medium instruction at full academic pace. Captio AI captions the professor in real time.

🔬Seminars and tutorials

Seminars and cvičení (tutorial sessions) where discussion is in Czech, often with English scientific terminology. Captio AI handles both without manual switching.

💻Online and recorded lectures

Recorded lectures on university e-learning portals or shared video files — play on speaker and Captio AI captions whatever is playing in real time.

📚Study groups

Study group sessions reviewing Czech lecture material in student accommodation. Captio AI captions whoever is speaking.

🌍Foreign-language and international courses

Guest lecturers from Moravia or Silesia whose Czech carries regional phonological patterns. Captio AI handles Bohemian, Moravian, and Silesian Czech varieties.

🎤Guest speakers and public talks

Online courses and webinars delivered by Czech universities in Czech or English. Captio AI captions any audio source in real time.

Performance

Most accurate and fastest models

Czech
90.3%

word accuracy

independent benchmark, 2025

< 200ms
you speak
captions

real-time captions

first word appears as you speak

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Captio AI in everyday use
Why Captio AI

Built for the pace and pressure of a real lecture

Follow without splitting your attention

Lip-reading and note-taking at the same time is an impossible cognitive load. Captio AI handles the following so you can direct all your attention to understanding what is being said.

Captions while the lecturer is still speaking

Words appear on your screen as they are said — not after the sentence ends. You stay in sync with the lecture rather than always being a beat behind.

Works in any lecture setting

Lecture halls, seminar rooms, online classes, study groups. Place the phone on your desk, point it toward the audio source, and Captio AI handles the rest.

A full transcript to study from

Record the lecture and upload it to Audio Transcription after class. Get a complete written record you can search, annotate, and revise from — at your own pace.

60+ languages

For international students, students studying abroad, or courses taught in a second language. Captio AI captions or translates in real time with no manual setup.

No advance notice needed

Official university captioning requires booking in advance and is not available for every session. Captio AI works for any lecture, any time, with no prior arrangement.

Czech

Why Czech is hard to understand

Vowel-less clusters

  • Czech has words with no vowels at all — no mouth opening to track in a lecture
  • Czech allows syllabic consonants to carry an entire word — 'strč prst skrz krk' (stick a finger through the throat) is a real Czech sentence with no vowels. Lecture vocabulary includes words like 'trh' (market) and 'smrt' (death) — consonant sequences delivered with no mouth-opening event. A deaf student tracking syllable positions loses the visual anchor that vowels provide.

Voicing assimilation

  • Czech voiced-voiceless pairs shift across word boundaries — invisibly
  • Czech applies regressive voicing assimilation: the voicing of one consonant changes to match the following consonant across word boundaries. These changes happen acoustically and are invisible on the lips. A deaf student predicting the next consonant from context will be wrong wherever assimilation applies.

Quantity distinction

  • Czech short and long vowels look identical on the lips but change meaning
  • Czech has five short and five long vowels — 'dráha' (track) versus 'draha' — where the length distinction changes meaning throughout a lecture. Vowel length is an acoustic property with no visual correlate. A deaf student watching Czech lip movements cannot distinguish short from long vowels, making quantity-minimal pairs a persistent source of ambiguity.

The ř sound

  • Czech ř — the rolled alveolar fricative — is produced behind near-closed teeth
  • The Czech phoneme /r̝/ — unique to Czech and Slovak — is a simultaneous trill and fricative produced with the tongue tip vibrating against the alveolar ridge. The lips barely move. In a Prague seminar, the ř sounds that distinguish Czech vocabulary produce almost no visible articulation from the front.

Bohemian-Moravian split

  • Prague Czech and Brno Czech sound different to a lip-reader tracking the same lecture text
  • Central Bohemian Czech (Prague) and Moravian Czech (Brno, Ostrava) differ in vowel realization and prosody. Silesian varieties from the northeast add a further set of vowel shifts. A deaf student calibrated to standard Prague Czech at Charles University finds Masaryk University Brno phonology different enough to require significant adjustment.

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The Challenge

300,000 hearing-impaired Czechs — in a system where sign language was recognised in 1998 but higher education remains a barrier

Up to 300,000 people in the Czech Republic have hearing impairment. Czech Sign Language (Český znakový jazyk) was officially recognised by the Czech parliament in 1998 — among the earlier European recognitions — with deaf people formally granted the right to education in their native language. However, the 1998 law did not extend its provisions to universities and courts, leaving Czech deaf students at higher education institutions without a statutory right to academic interpreting. A student at Charles University or Masaryk University who is deaf must individually negotiate accommodation with the disability office, and interpreter availability for specialised academic content is limited.

Genetic research on hearing loss in Moravia-Silesia confirms the condition's presence across Czech populations, with GJB2 gene variants accounting for a significant share of hereditary hearing loss cases. The Czech Deaf Association and the Czech Union of the Deaf (CUN) advocate for expanded services, but the university sector has been slow to adopt systematic captioning. Many deaf Czech students report that their first experience of comprehensive lecture access is through assistive technology rather than institutional provision.

The gap is felt most acutely in seminars and tutorials — the smaller, faster, discussion-based academic settings where Czech academic life is built and where no formal captioning exists at any Czech university. A deaf student at a Brno cvičení or a Prague seminar follows spoken Czech that moves faster than careful lip-reading allows. Captio AI captions Czech lecture and seminar speech in real time — in Prague or Brno, in a large amphitheatre or a small seminar room — so every academic setting is accessible without advance arrangement.

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Privacy

What you hear stays with you.

Gone the moment it ends

Captio AI processes your audio in real time and discards it immediately. Nothing is recorded. Nothing is kept.

Not a product

Your conversations are not something Captio AI sells, shares, or monetizes — to anyone, for any reason.

Not used to train anything

What you say in a doctor's appointment or a job interview never ends up in a training dataset. Not ours. Not anyone else's.

100% PRIVATE

Private by default

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Reviews

People love Captio AI

"Czech has words with no vowels. No mouth opening to track. Captio AI catches the consonant clusters acoustically and I read what was actually said. Prague seminars are accessible now."

Tereza H. 🇨🇿
tereza.h***@gmail.com
Hard of hearing, Charles University, Prague

"Fast technical Czech at CTU has zero pauses. The ř sound is invisible. Captio AI gets every phoneme right. My lecture notes went from guesses to facts."

Ondřej V. 🇨🇿
ondrej.v***@gmail.com
Deaf since birth, Czech Technical University, Prague

"Brno Moravian accent is different from Prague Czech I grew up reading lips for. Captio AI handles both. The regional difference is no longer a problem."

Markéta S. 🇨🇿
marketa.s***@gmail.com
Hard of hearing, Masaryk University, Brno

"The university disability office arranged one interpreter per week. I have lectures every day. Captio AI covers every session without paperwork or waiting."

Jakub N. 🇨🇿
jakub.n***@gmail.com
Hard of hearing, Palacký University, Olomouc

"Czech has words with no vowels. No mouth opening to track. Captio AI catches the consonant clusters acoustically and I read what was actually said. Prague seminars are accessible now."

Tereza H. 🇨🇿
tereza.h***@gmail.com
Hard of hearing, Charles University, Prague

"Fast technical Czech at CTU has zero pauses. The ř sound is invisible. Captio AI gets every phoneme right. My lecture notes went from guesses to facts."

Ondřej V. 🇨🇿
ondrej.v***@gmail.com
Deaf since birth, Czech Technical University, Prague

"Brno Moravian accent is different from Prague Czech I grew up reading lips for. Captio AI handles both. The regional difference is no longer a problem."

Markéta S. 🇨🇿
marketa.s***@gmail.com
Hard of hearing, Masaryk University, Brno

"The university disability office arranged one interpreter per week. I have lectures every day. Captio AI covers every session without paperwork or waiting."

Jakub N. 🇨🇿
jakub.n***@gmail.com
Hard of hearing, Palacký University, Olomouc

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FAQ

Frequently asked questions

Follow every lecture in Czech.

Captio AI is free to start

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