Captio AI
🦻 Accessibility + 💻 Productivity App

Korean live captions and productivity tool for communicating with deaf & hoh

For deaf and hard of hearing people.

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Captio AI app showing live captions

Download for free

Download on theApp Store
Use Cases

Every situation covered

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

👨‍👩‍👧Family conversations

Korean family meals — in Seoul, Busan, or a smaller family home — move fast, with hearing family members speaking in the casual register they use with each other. Captio AI captions what each person says in real time so a deaf or hard of hearing family member follows the full conversation without asking anyone to slow down or repeat.

💼As a hearing colleague

Korean workplaces have clear hierarchical registers — formal speech for seniors, casual for close colleagues. A hearing colleague moves naturally between these levels. Captio AI captions everything in real time so a deaf or hard of hearing colleague follows desk conversations, quick instructions, and hallway exchanges without missing a word.

❤️Partners and relationships

When your partner is deaf or hard of hearing and Korean is your home language. You speak naturally — the usual pace, the usual mix of formal and casual. Captio AI puts every word on their screen as you say it so nothing is lost between you.

🏠Living together

Everyday home life in a Korean household — questions across the living room, talking over a drama on TV, quick exchanges over breakfast. Captio AI covers the continuous low-key conversation that connects a household day by day.

🤝Introducing someone new

When a deaf or hard of hearing person meets a new hearing Korean speaker — at a family gathering, a hoesik dinner, or through a common friend. Set up Captio AI and the conversation starts naturally, without anyone needing to adjust how they speak.

👥Mixed group settings

Group settings — a chuseok gathering, a family meal, or a mixed social event — where some people are deaf or hard of hearing and some are not. Captio AI captions whoever is speaking so every person at the table is fully included in the conversation.

Performance

Most accurate and fastest models

Korean
95.7%

character 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

You talk. They follow. No adjustment needed.

You speak naturally

No slowing down, no special phrasing, no training required. Captio AI handles everything — you just talk the way you always do.

They read as you speak

Your words appear on their screen word by word while you are still talking. Not a summary after — the full sentence, in real time.

Works wherever you both are

Living rooms, offices, restaurants, social gatherings. No venue setup, no special conditions. Captio AI works anywhere you have a conversation.

No sign language from either side

You do not need to learn anything new. Neither do they. Captio AI bridges the gap without requiring any change to how either of you communicates.

Works with how you actually speak

Fast, accented, casual. Captio AI handles real speech — not just slow, clear dictation. You do not need to perform clarity for it to work.

Private by default

Your conversations are never recorded, stored, or shared. Audio is processed in real time and discarded immediately — nothing is kept.

Korean

Why Korean is hard to understand

Three-way stop contrast

  • Plain, tense, and aspirated Korean stops all look the same at the lips
  • Korean distinguishes plain, tense, and aspirated stops at the same place of articulation — /p/, /p'/, /pʰ/; /t/, /t'/, /tʰ/. The contrast is carried entirely by voice onset time and pitch — two acoustic cues that are invisible at the lips. 'Pa', 'ppa', and 'pha' look identical to a deaf lip-reader, yet they are different words.

Unreleased final consonants

  • Korean word endings close the mouth but never open again
  • Korean has seven permissible final consonants, but in natural speech, stop codas are unreleased before another consonant. The mouth closes, no burst follows, and the coda is phonetically invisible. A deaf lip-reader sees a closed mouth at word endings and cannot distinguish which final consonant was intended.

Gyeongsang tone-accent split

  • Busan and Seoul Korean are different lip-reading tasks
  • Standard Seoul Korean has relatively flat pitch; Gyeongsang Korean (Busan, Daegu) is a pitch-accent dialect where words change meaning with different pitch contours — a dimension that is entirely auditory. A deaf lip-reader familiar with Seoul-standard speech faces an added invisible layer when a hearing family member from the Gyeongsang region speaks.

Casual syllable compression

  • Korean casual speech drops entire syllables that a lip-reader expects to see
  • Korean casual speech drops syllables aggressively: '어디 가?' becomes '드가?', '뭐야?' becomes '먀?'. These contractions have no standard written form — a deaf lip-reader's learned visual patterns do not match what a hearing family member actually produces at a family dinner or at home.

Koreanized English loanword density

  • English loanwords in Korean sound like neither English nor traditional Korean
  • Modern Seoul Korean is dense with 외래어 (English loanwords) fully absorbed into Korean phonology — 'ice cream', 'computer', 'air conditioning' become '아이스크림', '컴퓨터', '에어컨'. The lip shapes don't match English pronunciation or traditional Korean — creating a third visual category a deaf lip-reader must navigate.

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The Challenge

Hearing loss in South Korea: a common condition, a persistent daily gap

A nationwide population-based study found that severe to profound hearing loss affected 0.46% of South Korea's population in 2015 — approximately 237,000 people (PMC6028585). But clinically significant hearing loss extends well beyond this threshold: a separate study found that 37.4% of South Koreans have minimal hearing loss, and the Frontiers in Public Health situational analysis (2023) identified significant gaps in rural-urban access to ear care. Hearing impairment is more prevalent in rural areas — 1.4 times higher than urban — and in men, reflecting occupational noise exposure across South Korea's industrial sectors.

South Korea's National Health Insurance has subsidised hearing aids for registered individuals with severe hearing loss since 1989, and subsidies increased to approximately US$1,000 in 2015. But the programme covers only the most severe end of the spectrum. People with moderate hearing loss — the majority of those with a clinically significant condition — receive no financial support for hearing aids and often go undiagnosed for years. Korean Sign Language (KSL) exists as a recognised language with a small community of users, but for the large majority of deaf and hard of hearing Koreans, daily communication with hearing family members depends on informal strategies rather than any structural support.

South Korea has one of the world's most rapidly ageing populations, and hearing loss rises steeply with age. As Korean households increasingly include elderly members with significant hearing impairment, the communication gap at family tables grows — while the technology to bridge it has remained limited to formal hearing aid provision. Captio AI captions natural Korean speech in real time, at a chuseok table in Seoul or a family dinner in Busan, so a deaf or hard of hearing family member reads exactly what their hearing relatives are saying — at natural pace, in their home dialect.

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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 husband's casual speech — the syllables he drops, the contractions — was impossible for me to lip-read consistently. Captio AI reads it correctly even at full speed. I follow what he actually says now, not an approximation."

Ji-yeon K. 🇰🇷
jiyeon.k***@gmail.com
Deaf since childhood, hearing husband speaks Seoul casual Korean, Seoul

"Busan dialect has a pitch accent I never learned to read. Family gatherings were mostly lost to me. Captio AI reads my family's Gyeongsang Korean accurately and I follow the table for the first time at chuseok."

Minjun P. 🇰🇷
minjun.p***@gmail.com
Hard of hearing, hearing family speaks Gyeongsang Korean, Busan

"Office Korean moves between very formal speech with managers and casual with colleagues. I was managing formal interactions but losing the casual exchanges. Captio AI handles both registers and I follow the full workday now."

Soyeon L. 🇰🇷
soyeon.l***@gmail.com
Deaf, hearing colleagues speak standard Seoul Korean, Seoul

"My children's Korean is full of English words pronounced in Korean — I did not recognise half of them. Captio AI captions the whole sentence including the loanwords and I understand what they are saying without asking them to switch to older Korean for me."

Hyunwoo C. 🇰🇷
hyunwoo.c***@gmail.com
Hard of hearing at 61, hearing children speak fast modern Korean dense with English loanwords, Incheon

"My husband's casual speech — the syllables he drops, the contractions — was impossible for me to lip-read consistently. Captio AI reads it correctly even at full speed. I follow what he actually says now, not an approximation."

Ji-yeon K. 🇰🇷
jiyeon.k***@gmail.com
Deaf since childhood, hearing husband speaks Seoul casual Korean, Seoul

"Busan dialect has a pitch accent I never learned to read. Family gatherings were mostly lost to me. Captio AI reads my family's Gyeongsang Korean accurately and I follow the table for the first time at chuseok."

Minjun P. 🇰🇷
minjun.p***@gmail.com
Hard of hearing, hearing family speaks Gyeongsang Korean, Busan

"Office Korean moves between very formal speech with managers and casual with colleagues. I was managing formal interactions but losing the casual exchanges. Captio AI handles both registers and I follow the full workday now."

Soyeon L. 🇰🇷
soyeon.l***@gmail.com
Deaf, hearing colleagues speak standard Seoul Korean, Seoul

"My children's Korean is full of English words pronounced in Korean — I did not recognise half of them. Captio AI captions the whole sentence including the loanwords and I understand what they are saying without asking them to switch to older Korean for me."

Hyunwoo C. 🇰🇷
hyunwoo.c***@gmail.com
Hard of hearing at 61, hearing children speak fast modern Korean dense with English loanwords, Incheon

Download for free

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FAQ

Frequently asked questions

Make every conversation work — for both sides in Korean.

Captio AI is free to start

Download for free

Download on theApp Store