Captio AI
🦻 Accessibility + 💻 Productivity App

Vietnamese 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

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Use Cases

Every situation covered

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

👨‍👩‍👧Family conversations

Vietnamese family meals — in Hà Nội, Hồ Chí Minh City, or Đà Nẵng — are often fast and multi-threaded, with hearing family members talking over each other in regional Vietnamese. Captio AI captions what each person says in real time so a deaf or hard of hearing family member follows the full table without asking anyone to repeat.

💼As a hearing colleague

Vietnamese workplaces run in a fast mix of formal and casual Vietnamese for everyday exchanges. A hearing colleague speaks at their normal pace in whichever register fits the moment. Captio AI captions what they say so a deaf or hard of hearing colleague follows corridor talk, quick questions, and team discussions without missing a word.

❤️Partners and relationships

When your partner is deaf or hard of hearing and Vietnamese is the language you speak at home. You talk naturally — the usual pace and register. Captio AI puts your words on their screen word by word so nothing is lost between you.

🏠Living together

Everyday home life in a Vietnamese household — calling across the apartment, talking during the evening news, quick exchanges over a family meal. Captio AI covers the daily thread of home communication that a deaf or hard of hearing family member might otherwise have to guess at.

🤝Introducing someone new

When a deaf or hard of hearing person meets a new hearing Vietnamese speaker for the first time — at a family gathering, a community event, or a Tết celebration. Captio AI captions naturally so the conversation starts without any awkward adjustment.

👥Mixed group settings

Group settings — a Tết family gathering, a large multi-generation meal, or a neighbourhood 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 part of the same conversation.

Performance

Most accurate and fastest models

Vietnamese
94.6%

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

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.

Vietnamese

Why Vietnamese is hard to understand

Six tones, zero visual signal

  • The same syllable means six things — and all six look identical at the lips
  • Vietnamese has six lexical tones — level, rising, falling, broken, creaky, low — that completely change word meaning. The same syllable 'ba' means six different things depending on its pitch contour. Tone is entirely auditory; the lip movement is identical for all six. A deaf lip-reader has no visual access to the tonal information that separates meaning from meaning.

Northern vs. Southern tone merger

  • Northern and Southern Vietnamese are different lip-reading tasks
  • Standard Northern Vietnamese (Hà Nội) preserves more tone contrasts and initial consonant distinctions. Southern Vietnamese (Hồ Chí Minh City) merges some tones and neutralizes consonants (/v/→/j/, initial /dz/→/j/). A deaf person who lip-reads one variety faces a shifted phonological map when a hearing family member from the other region speaks.

Unreleased final stops

  • Vietnamese word endings close the mouth but give no other signal
  • Vietnamese syllables may end in /p/, /t/, /k/ — but these stops are unreleased in natural speech. The mouth closes, but there is no audible or visible burst. A deaf lip-reader sees a closed mouth and cannot distinguish /p/, /t/, and /k/ at word endings — collapsing distinctions that change meaning.

Central Vietnamese dialect

  • Huế Vietnamese follows different rules than either Northern or Southern
  • The Huế and surrounding Central varieties have notably different tone realization and consonant inventory from both Northern and Southern Vietnamese. Hearing family members from Central Vietnam — a culturally significant region — produce speech that is hard for a deaf person lip-reading either standard variety to follow.

Syllable stream at speed

  • Fast Vietnamese produces an unbroken stream with no visible word breaks
  • Vietnamese is broadly syllable-timed, but in fast natural speech, unstressed function syllables reduce and blur at their boundaries. Lip-reading across a rapid syllable stream without the auditory anchor of tone — the single biggest disambiguation tool in Vietnamese — makes tracking meaning very difficult.

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The Challenge

Hearing loss in Vietnam: high rates, limited data, limited support

Vietnam's Ministry of Health reports that between 1,200 and 1,400 children are born with hearing impairments every year — a rate that places Vietnam among countries with high congenital hearing loss incidence. Overall, more than 6.7 million people in Vietnam have disabilities of any kind, representing 6.34% of the population (MOLISA data). But disability-specific data in Vietnam, especially for those with hearing and print disabilities, remains seriously incomplete. The UN Development Programme noted in 2024 that making people with disabilities more visible in Vietnam's national database is an active and unresolved policy challenge.

Vietnam has a legal framework for disability inclusion, but welfare policies toward people with disabilities have significant limitations in providing sustainable services and creating inclusive settings for social participation (PMC4085279). Vietnamese Sign Language (VNSL) exists but is not standardised, and interpreter provision for everyday social settings — family conversations, workplaces, neighbourhood life — is effectively absent outside major cities. For a deaf or hard of hearing person in Hà Nội, Hồ Chí Minh City, or a provincial town in the Mekong Delta, the communication gap at home is privately managed and structurally unsupported.

Vietnam's population is also ageing, and hearing loss rises steeply with age. As the proportion of elderly hearing-impaired people in Vietnamese households grows, the communication gap will become more common at family tables across the country — while the support infrastructure remains thin. Captio AI captions natural Vietnamese speech in real time, at a Tết meal in Hà Nội or an evening conversation in Hồ Chí Minh City, so a deaf family member reads exactly what their hearing relatives are saying — tones, dialect, and pace included.

Download for free

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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

"Northern Vietnamese has distinct tones I cannot access at all. Captio AI reads my husband's words and the meaning is there on the screen — I do not have to guess from context and expression alone anymore."

Linh N. 🇻🇳
linh.n***@gmail.com
Deaf since birth, hearing husband speaks Hà Nội Vietnamese, Hà Nội

"Southern Vietnamese merges some tones that Northern Vietnamese keeps separate. My family's speech was a blur. Captio AI reads the Southern variety accurately and I follow what my parents are saying at family meals."

Minh T. 🇻🇳
minh.t***@gmail.com
Hard of hearing, hearing family speaks Southern Vietnamese, Hồ Chí Minh City

"Office Vietnamese is more formal but still fast. I was catching about half. Captio AI captions what my colleagues say as they say it and I participate in conversations instead of asking for written summaries after."

Hoa P. 🇻🇳
hoa.p***@gmail.com
Deaf, hearing colleagues speak standard Vietnamese in the office, Hà Nội

"My children use English words constantly in Vietnamese sentences. I was lost in both languages. Captio AI handles the mixing and I understand what they are saying — the whole sentence, not just the Vietnamese parts."

Thành V. 🇻🇳
thanh.v***@gmail.com
Hard of hearing at 59, hearing children speak fast modern Vietnamese mixed with English, Hồ Chí Minh City

"Northern Vietnamese has distinct tones I cannot access at all. Captio AI reads my husband's words and the meaning is there on the screen — I do not have to guess from context and expression alone anymore."

Linh N. 🇻🇳
linh.n***@gmail.com
Deaf since birth, hearing husband speaks Hà Nội Vietnamese, Hà Nội

"Southern Vietnamese merges some tones that Northern Vietnamese keeps separate. My family's speech was a blur. Captio AI reads the Southern variety accurately and I follow what my parents are saying at family meals."

Minh T. 🇻🇳
minh.t***@gmail.com
Hard of hearing, hearing family speaks Southern Vietnamese, Hồ Chí Minh City

"Office Vietnamese is more formal but still fast. I was catching about half. Captio AI captions what my colleagues say as they say it and I participate in conversations instead of asking for written summaries after."

Hoa P. 🇻🇳
hoa.p***@gmail.com
Deaf, hearing colleagues speak standard Vietnamese in the office, Hà Nội

"My children use English words constantly in Vietnamese sentences. I was lost in both languages. Captio AI handles the mixing and I understand what they are saying — the whole sentence, not just the Vietnamese parts."

Thành V. 🇻🇳
thanh.v***@gmail.com
Hard of hearing at 59, hearing children speak fast modern Vietnamese mixed with English, Hồ Chí Minh City

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FAQ

Frequently asked questions

Make every conversation work — for both sides in Vietnamese.

Captio AI is free to start

Download for free

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