Dual subtitles player: watch your own video online
How it works
- Load your video. Drag a file into the player or choose it on your computer.
- Add subtitles. Load a subtitle file in the language you learn and, if you have it, a second file in your own language.
- Watch and translate words. Both subtitles appear together. Hover over a word to see its translation and save it to your word list.
- Adjust the delay if needed. If the subtitles come a little late or early, shift them with the plus and minus buttons in the row of those subtitles. Hold Shift for smaller steps.
Supported formats
Video: MP4, WebM, MKV, MOV, AVI, TS and VOB. Most files play in your browser's own engine. When the browser can't play a file by itself, for example an MKV with AC-3 sound or with several audio tracks, the player opens it with a built-in engine. You can choose the audio track with the headphones button () and jump between chapters from the menu of the list button ().
Subtitles: SRT, VTT, ASS (SSA) and TTML files. If a file has a different extension, the player checks what is inside it. You can play an MKV with external subtitles or play a video with embedded subtitles: text subtitles inside MKV and MP4 files appear in a list under the player. Picture subtitles from Blu-ray (PGS) and DVD (VobSub) are turned into text in your browser, in 29 languages, so you can translate their words too.
Old Flash video (FLV) and Windows Media (WMV) files are not supported. Re-encode them to MP4 (H.264 with AAC audio).
The player doesn't search for subtitles. Use the file that came with your video or one you downloaded.
Two subtitles and word translation
See two languages at once: the one you learn and your own. Hover over a word to see its translation and save it. The video pauses while you read.
Subtitle translation is available on all paid plans.
Fix out-of-sync subtitles
If your subtitles are out of sync, fix the delay with the plus and minus buttons in the row of those subtitles. One step is 0.5 second; hold Shift for 0.1 second.
The main and the second subtitles have their own delay, so you can sync subtitles online without editing the file. The delay is saved in your browser.
Learn a language with your own movies
Films and series you already own are good study material: you know the story, and the dialogue is real speech. Put the subtitles in the language you learn on top and your own language below, and watch without stopping to look words up. Read more in how double subtitles help you learn.
What is sent to our servers
Your video and subtitle files are not uploaded to a server. They stay in your browser.
When you translate a word, we receive the word, the subtitle phrase around it, the time in the video and the languages. If you sign in, the words you translate are saved to your word list. You can turn off autosave in the settings.
The player or the extension
The player is for files on your computer. The InterSub extension adds dual subtitles and the pop-up dictionary to streaming services, courses and websites, and it works together with this page: if it is installed, the player uses it.
Plans and limits
You can translate 15 words per month for free. Subtitle translation is available on all paid plans; see plans and prices.
Phones and tablets
The player is built for computers. On a tablet, it works in landscape orientation; tap a word to translate it. On a phone, the page asks you to open it on a computer.
Frequently asked questions
What are dual subtitles?
Two subtitle lines shown at the same time, usually the language you learn and your own. You hear the original, read it, and see the translation under it.
Can I watch a local video with subtitles in my browser?
Yes. Open this page, drag your video into the player and add an SRT, VTT or ASS file. Nothing is installed and nothing is uploaded.
How do I show two subtitles at the same time?
Load two subtitle files: one as main subtitles and one as second subtitles. The player shows both subtitles together.
Does the player upload my video or subtitle file?
No. The video and the subtitle files stay in your browser. Only the words you translate, with the phrase around them, are sent for translation.
Which video and subtitle formats are supported?
Video: MP4, WebM, MKV, MOV, AVI, TS and VOB. Subtitles: SRT, VTT, ASS and TTML files, and subtitles inside MKV and MP4 files, including picture subtitles from Blu-ray and DVD. FLV and WMV files are not supported.
Why does my video play without sound?
Check the volume and the audio track first: a film can have several tracks, and you can choose one with the headphones button (). Sound that the browser can't play, such as AC-3, is played by the player's built-in engine, so you don't need to convert the file. If a video still has no sound, re-encode it to MP4 with AAC audio and write to us with the contact button.
How do I sync subtitles that are late or early?
Use the plus and minus buttons in the row of those subtitles under the player. Each file has its own delay. Hold Shift to move in steps of 0.1 second.
Do I need to install the extension or sign up?
No. The player works in your browser without an account. The extension is optional and adds the same features to other websites. Sign in if you want your translated words saved.
How do I translate a word while watching?
Hover over the word in the subtitle line. The translation opens in a small card where you can save the word.
Is it free? How many words can I translate?
Yes. You can translate 15 words per month for free. Paid plans raise the limit and add subtitle translation.
Will the player remember my video and subtitles?
Yes. It keeps your subtitles, the playback position and the subtitle delay in your browser. For the video itself, you may be asked to choose the same file again.
Can I learn a language with my own movies and subtitles?
Yes, that's what the player is for. Watch with subtitles in the language you learn, hover over the words you do not know and save them.
Does it work on a phone?
Not yet: the player is built for computers, so open the page on a computer. On a tablet, the player works in landscape orientation.