Live bilingual captions · macOS 26+

Any video.
Real-time bilingual captions. Zero cloud.

KenjaBrowser is a Mac browser that shows original speech and translation together as live subtitles — on YouTube, news sites, courses, and live streams. The AI runs entirely on your Mac: no uploads, no tracking, no data collection.

Download for Mac See it in action

On-device AI No audio uploads Ad blocker built in Free to start

CC EN → 日本語

● LISTENING · ON-DEVICE 0 ms CLOUD LATENCY

// the same bar floats above any video, in any language pair

How it works

Three steps. No setup. No accounts.

STEP / 01

Play any video

Open YouTube, a news site, an online course, or a live stream in KenjaBrowser and press play.

STEP / 02

Pick a language pair

Choose source and target languages — for example English → 日本語 or 한국어 → English — and switch anytime.

STEP / 03

Read live captions

The floating caption bar shows original speech and translation together, in real time, as the video plays.

Features

A private browser built for watching — and learning

Everything runs locally on your Mac. KenjaBrowser is deliberately lean, which makes it the ideal secondary browser for video, language learning, and private browsing.

Real-time bilingual captions

Live subtitles for any web video: original speech and translation displayed side by side, updating as people speak.

YouTubeCoursesLive streamsNews

100% on-device AI

Speech recognition and translation run on your Mac. Your audio never leaves the device — nothing to upload, nothing to leak.

No cloudNo trackingData Not Collected

14 + 25 languages

Speech recognition in 14 languages, translation into 25 — from English, Chinese, and Japanese to Spanish, Korean, and Thai.

Instant pair switchingBilingual / single-line modes

Built-in ad blocker

An integrated content blocker auto-skips video ads and popups on most websites — cleaner pages, faster loading.

Tracker blockingLocal filter rules

Touch ID lock & private bookmarks

Lock the whole browser with Touch ID and keep bookmarks in an encrypted vault. No history page is kept, ever.

AES-GCM vaultBiometric lock

Your ideal secondary browser

Simple, clean, and fast. Use it alongside your main browser for video, study sessions, and anything you want kept private.

LightweightNative WebKitmacOS 26

Screenshots

See KenjaBrowser in action

Real screenshots from the Mac app — live bilingual captions, ad blocking, and a clean interface that stays out of the way.

01 / LIVE CAPTIONS

Bilingual subtitles on any video

A YouTube video with the floating caption bar showing English speech and its Chinese translation together — recognized and translated on-device, in real time.

KenjaBrowser showing a YouTube video with a floating bilingual caption bar translating English speech to Chinese in real time

02 / ALWAYS VISIBLE

A floating caption bar you can style

Keep captions exactly where you want them. Choose fonts, colors, size, and display mode — bilingual, translation only, or original only.

The floating real-time AI bilingual subtitles bar overlaid on a video in KenjaBrowser

03 / AD BLOCKER

Ads auto-skipped, popups gone

The built-in ad blocker skips video ads and suppresses popups on most websites, so pages load cleaner and videos start sooner.

04 / PRIVACY

No history page. No accumulated records.

KenjaBrowser keeps no browsing history page and no viewing records. Combined with on-device processing, there is simply nothing to expose.

KenjaBrowser privacy screen showing no history page and no accumulated browsing records

05 / CLEAN BY DESIGN

Simple, clean, ideal as a secondary browser

A minimal new-tab page and a distraction-free interface. It is the browser you reach for when you just want to watch, read, and study.

KenjaBrowser's simple clean new tab page on macOS, designed as a lightweight secondary browser

Privacy first

Your audio never leaves your Mac.

Speech recognition, translation, and browsing all happen locally. KenjaBrowser has no backend, no analytics SDK, and nothing to collect.

×No audio uploads ×No cloud processing ×No tracking ×No data collection ×No history page

Read the privacy policy →

FAQ

Frequently asked questions

What is KenjaBrowser?

KenjaBrowser is a secondary browser for macOS that adds real-time bilingual captions to any online video. Its speech recognition and translation run entirely on your Mac using on-device AI, so you can watch YouTube, news, courses, and live streams with the original speech and a translation displayed together as subtitles.

Does KenjaBrowser upload my audio to a cloud server?

No. Speech recognition and translation are processed locally on your device. There are no audio uploads, no cloud processing, no tracking, and no data collection. The App Store privacy label is Data Not Collected.

Which websites and videos are supported?

Any website that plays video in the browser: YouTube, news sites, online courses, live streams, and more. Just play the video and turn on captions.

Which languages are supported for live captions?

Speech recognition supports 14 languages including English, Chinese (Simplified and Traditional), Japanese, Korean, French, German, Spanish, Russian, Arabic, Thai, Vietnamese, Indonesian, Italian, and Portuguese. Translation supports 25 languages, and you can switch language pairs anytime.

Is KenjaBrowser free?

The app is free to download and includes all core browser features with a starter allowance for bilingual captions. Kenja PRO optionally unlocks unlimited captions — plans and pricing are shown in the app.

Which Macs can run KenjaBrowser?

KenjaBrowser requires macOS 26.0 or later. On first use of live captions, macOS asks for a one-time Screen & System Audio Recording permission that covers only the app's own audio — no system-wide capture, no screen content, and no microphone input is ever recorded.

Any video. Real-time bilingual captions. Zero cloud.