Japanese game streams and playthroughs with English subtitles (free)

Published: 2026-09-16 ・ Updated: 2026-11-03

Works in Chrome or Edge on a computer (Firefox: through a microphone or audio input; the add-on covers YouTube and Twitch; not on phones). Japanese ⇄ English only.

Japanese game streams and playthroughs are worth watching: commentary on games not yet released in English, speedruns of Japan-only titles, a streamer reacting to a story you know.

But there are no English subtitles, and translated clips, if any, arrive days later.

This guide shows how to get English subtitles on a Japanese game stream or playthrough playing in your browser, live or recorded, for free, without installing anything.

In short: add the free LiveSub extension for Chrome or Edge on your computer, press its icon on the stream's tab, and set “Translate from / to” to Japanese → English in the LiveSub tab that opens. The commentary appears as Japanese and English subtitles over the video, about one to two seconds behind, with no sharing dialog. Without the extension, open LiveSub in another tab and share the stream's tab instead. Loud game audio lowers accuracy, and on-screen text is not translated.

Open LiveSub and try it

What you need and how it works

• Chrome or Microsoft Edge on a computer. In Firefox, LiveSub listens through a microphone or a loopback audio input (such as Windows Stereo Mix); on YouTube and Twitch, LiveSub for Firefox turns the video's audio into subtitles directly. Safari uses the same input method but is untested
• Not a phone or tablet. Mobile browsers cannot share tab audio
• The stream open in a browser tab, not in a desktop app
• A one-time download of the speech recognition model. For Japanese, the Balanced setting is about 670MB; after the first time, it is loaded from your browser's storage

No account, no extension, no payment, and no time limit.

Using Firefox? Firefox cannot share a tab's audio, so LiveSub listens through a microphone or an audio input instead. Open LiveSub in Firefox, play the video in another tab, and press "Start (mic or audio input)" on the LiveSub page. Allow microphone access when the browser asks. If your computer has a loopback input (such as Windows Stereo Mix), LiveSub picks it automatically; otherwise it listens through the microphone to the sound from your speakers (headphones will not work). There is no sharing dialog. On YouTube and Twitch, LiveSub for Firefox turns the video's audio into subtitles directly: press "Add to Firefox — it's free" to install it, play the video in another tab, and press "Start (YouTube / Twitch tab)"; the subtitles appear over the video.

LiveSub is a website. You share one browser tab's audio with it. It recognises the Japanese speech on your own computer, translates it with Chrome's built-in on-device translator, and shows the Japanese and the English as subtitles. Your audio is never uploaded anywhere.

Because it works from sound, it subtitles what you can hear: the streamer, guests, and voiced game dialogue. Text on the screen is not translated: menus, item descriptions and in-game captions stay as they are.

Step by step

1. Set the direction and try the how-to video

Open LiveSub in Chrome. Under "Translate from / to", choose Japanese → English. Japanese uses a different recognition model, and if you leave it on English → Japanese you get garbled text instead of subtitles.

Press "Try the how-to video (no sharing)". It plays a short how-to video in Japanese and shows subtitles without sharing any tab, and it gets the one-time download out of the way.

2. Choose a recognition setting

Under "Recognition setting", the options for Japanese are:

• Balanced: the recommended starting point. It keeps up with live speech
• Lighter: for when subtitles fall behind. It mishears a little more
• Lightest: for older computers. It mishears a lot

You can change the setting while the stream is running.

3. Share the stream's tab

Open the stream in another tab. Back in LiveSub, press "Start (share a tab)". In Chrome's sharing dialog:

1. Pick the "Chrome Tab" section at the top
2. Choose the tab playing the stream
3. Tick "Also share tab audio" at the bottom left
4. Press Share

4. Watch

Subtitles appear about one to two seconds after the words are spoken. On the first run, they start once the model has finished loading.

Put game terms in the word list

This is the single most useful thing you can do for game streams. Speech recognition is bad at names, and games are made of them: character names, place names, item and skill names, boss names, the game's own title, and the streamer's nickname. Left alone, each of these comes out differently every time it is said.

Open "Word list" and add the correct spellings, one per line. Japanese entries need at least 3 characters, English ones 4. Add each form you expect to hear, for example a full name and the short form. To choose how a name appears in the translation too, write it as "たなか = Tanaka".

Anything recognition mishears is corrected to your spelling, and it also fixes the hiragana and katakana mix-ups that recognition is prone to.

Watching comfortably

Reading over a fullscreen stream

Press "Show in a floating window". The subtitles move into a small window that stays on top of everything else, so you can put the stream in fullscreen and still read them.

Drag it to an edge where it does not cover the action, and switch the display to "Translation only" if you want it compact. You can scroll back to earlier lines.

If you are playing a game yourself

Speech recognition uses the GPU too. If you are playing on the same computer and your game starts stuttering, tick "Don't use the GPU (if games or video stutter)".

Recognition runs on the CPU instead, a little slower, but it stops competing with your game.

Live streams and recorded playthroughs

Live streams: there is no time limit, because nothing runs on a server. A six-hour stream is fine.

Recorded playthroughs: the subtitles follow whatever is playing. Pause, and they pause; rewind, and the line is subtitled again, so you can replay a bit of commentary you missed.

For either, "Download transcript" saves the whole session as a text file with timestamps, the Japanese and the English side by side.

Honest limits

• Loud BGM and sound effects reduce accuracy. Quiet menus and chatting segments come out well; boss fights with music at full volume do not
• The subtitles do not say who is speaking. The streamer's commentary and the game's voiced lines appear in the same stream of text
• Text on screen is not translated. Only the audio is
• Collabs with several people talking at once lose the overlapping parts
• It is machine translation. You get the gist; jokes, slang and wordplay often do not survive
• Names are the weak point even with the word list
• About one to two seconds of delay
• Computer only. It needs Chrome or Edge on a desktop or laptop (Firefox: through a microphone or audio input)

Wrapping up

You can follow a Japanese game stream or playthrough as it plays, with the commentary in Japanese and English. Add the game's names to the word list before you start, and chatting segments will read best.

Open LiveSub on your computer and press "Try the how-to video (no sharing)" first, then share the stream's tab.

About this guide: written by the maker of LiveSub. Steps, button names and figures are checked against the LiveSub app as of the date above. If something is wrong, please tell us through the contact page.

Open LiveSub and try it