Captio AI
🦻 Accessibility + 💻 Productivity App

German 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

Lecture halls at LMU Munich, Humboldt Berlin, Heidelberg, or TU Dresden seat hundreds of students. Professors deliver academic German at full speed. Place the phone on the desk facing the PA system. Captio AI captions the lecture from any row.

🔬Seminars and tutorials

German university seminars (Seminare) run as discussion sessions with students presenting and arguing in fast academic German. Captio AI captions whoever is speaking so you follow every argument without losing your place.

💻Online and recorded lectures

Recorded lectures on university portals, RWTH Aachen MOOC platforms, or Zoom session replays. Auto-captions miss fast academic German. Put the recording on speaker and point Captio AI at the audio for accurate captions.

📚Study groups

Revision groups in the library, Lernräume, or student flats. Academic German at conversational speed, mixing standard German with regional varieties. Captio AI follows whoever is explaining.

🌍Foreign-language and international courses

Erasmus and international students at German-medium universities, or German students following English-medium seminars. Live Translator captions in real time so language is not the access barrier.

🎤Guest speakers and public talks

Visiting academics and guest lecturers. German university talks draw speakers from Austria, Switzerland, and across Germany — each with different regional phonetics. Captio AI covers any speaker at any venue.

Performance

Most accurate and fastest models

German
93%

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.

German

Why German is hard to understand

Compound word collapse

  • German compounds merge into single unbroken lip shapes — impossible to segment without sound
  • German routinely joins multiple words into a single compound: Rechtswissenschaft, Vorlesungsverzeichnis, Haushaltsausschuss. On the lips, the compound reads as one continuous, indistinct movement. In a lecture, these long compounds carry the exact technical meaning of the sentence — and they are the words most likely to defeat lip-reading entirely.

Connected speech reduction

  • Unstressed syllables reduce or delete entirely in natural academic German
  • German unstressed vowels reduce toward schwa, and in fast academic delivery entire syllables drop. The definite article 'das' becomes 'd'', 'haben' becomes 'ham', 'werden' becomes 'wern'. The written form and the lip-read form diverge substantially in continuous lecture speech. Research on German lip-reading confirms that sentence frequency and articulation quality are primary determinants of comprehension — and natural lecture delivery is neither slow nor careful.

Regional accent divergence

  • German universities draw professors from Austria, Switzerland, and all 16 German states — each with distinct lip profiles
  • Hochdeutsch is the standard, but lecture delivery varies enormously: Bavarian fronts certain vowels, Saxon softens consonants, Swiss German has entirely different prosody, and northern Low German influence produces different fricative realizations. A deaf student calibrated to one variety encounters different lip patterns in each lecture from a different regional speaker.

Obstruent neutralization

  • German final obstruent devoicing removes auditory contrasts that never existed visually
  • German devoices all obstruents in syllable-final position: /d/ → /t/, /b/ → /p/, /g/ → /k/, /z/ → /s/. The acoustic contrast disappears. On the lips, these contrasts were never visible to begin with — /d/ and /t/ are visually identical. In a lecture, this means a deaf student cannot distinguish plural from singular or verb tense from lip shape alone.

Academic register gap

  • German academic vocabulary layers Latin and Greek roots over everyday speech — unrecognizable on the lips
  • German lectures use a formal academic register with Latin-derived terminology (Paradigmenwechsel, Äquivalenzprinzip, epistemologisch) that sounds and looks completely different from colloquial German. Even a fluent deaf German speaker accustomed to everyday speech encounters unfamiliar lip shapes when the professor shifts to academic terminology.

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The Challenge

16 million Germans with hearing loss — and university lecture halls built around hearing

Germany's Gutenberg Health Study, published in 2023, found that among adults aged 25–86, prevalence of mild hearing impairment stood at 28.2% and moderate impairment at 10.1%, with a total of 38.7% of the study population experiencing some degree of hearing loss. These figures are consistent with broader German epidemiological data showing approximately 16 million people with significant hearing difficulty — one in five Germans. Despite Germany's reputation for robust social infrastructure, hearing aid uptake remains at approximately 37%, among the lower rates in Western Europe.

German universities are legally required to provide accessibility under Sozialgesetzbuch IX (Social Code Book IX) and the Behindertengleichstellungsgesetz (BGG, Federal Disability Equality Act), but the practical provision of real-time captioning in lecture halls is inconsistent. Most German universities offer accessibility through Disabilities Officers (Behindertenbeauftragte) but do not systematically provide live captions for deaf and hard of hearing students in ordinary lectures. This gap is documented by the Informations- und Beratungsstelle Studium und Behinderung (IBS), which coordinates between disability organizations and German higher education. Deaf students who cannot use sign language interpreters must typically negotiate accessibility individually with each faculty.

The Deutscher Gehörlosenbund (DGB, German Association of the Deaf) represents approximately 80,000 prelingually deaf people in Germany. The association has consistently documented that deaf and hard of hearing students face structural barriers in higher education — barriers that exist not in formal policy but in the gap between policy and implementation. German Sign Language (Deutsche Gebärdensprache, DGS) has been legally recognized since 2002, yet qualified DGS interpreter provision for university lectures remains geographically uneven, with rural institutions and specialized technical universities particularly underserved.

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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

"My LMU professor speaks fast Bavarian-accented German packed with compound terms. Captio AI handles both the accent and the word length. I finally follow lectures instead of transcribing them afterward."

Lena B. 🇩🇪
lena.b***@gmail.com
Hard of hearing, Munich

"Seminar discussions in fast Berlin German, multiple speakers, academic vocabulary. Captio AI captions whoever is talking. I contribute to seminars now instead of staying silent."

Jonas R. 🇩🇪
jonas.r***@gmail.com
Deaf student, Berlin

"Austrian German in lectures sounds different from Hochdeutsch on the lips. Captio AI handles it accurately. I follow Vienna University lectures without a separate captioning arrangement."

Sophie M. 🇦🇹
sophie.m***@gmail.com
Hard of hearing, Vienna

"ETH lectures mix Swiss-influenced German with dense technical vocabulary. Captio AI captions both without losing accuracy. Engineering lectures are finally accessible for me."

Tobias K. 🇨🇭
tobias.k***@gmail.com
Hard of hearing, Zurich

"My LMU professor speaks fast Bavarian-accented German packed with compound terms. Captio AI handles both the accent and the word length. I finally follow lectures instead of transcribing them afterward."

Lena B. 🇩🇪
lena.b***@gmail.com
Hard of hearing, Munich

"Seminar discussions in fast Berlin German, multiple speakers, academic vocabulary. Captio AI captions whoever is talking. I contribute to seminars now instead of staying silent."

Jonas R. 🇩🇪
jonas.r***@gmail.com
Deaf student, Berlin

"Austrian German in lectures sounds different from Hochdeutsch on the lips. Captio AI handles it accurately. I follow Vienna University lectures without a separate captioning arrangement."

Sophie M. 🇦🇹
sophie.m***@gmail.com
Hard of hearing, Vienna

"ETH lectures mix Swiss-influenced German with dense technical vocabulary. Captio AI captions both without losing accuracy. Engineering lectures are finally accessible for me."

Tobias K. 🇨🇭
tobias.k***@gmail.com
Hard of hearing, Zurich

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FAQ

Frequently asked questions

Follow every lecture in German.

Captio AI is free to start

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