Subtitle Editor Online (SRT, VTT, ASS)
A subtitle editor online that works against your own video: fix typos, retime lines by dragging them on the waveform, split or merge them, or write an SRT from scratch while the video plays. Export SRT, VTT or ASS. Nothing to install and nothing uploaded, because your video and subtitles never leave the browser.
- Runs on your device
- Browser APIs
- Web Audio
- Works offline
Updated
How to edit an SRT file
Step 1: Drop your video (or audio) and its subtitle file on the box above. Drop only the video to start from scratch.
Step 2: Click a line to edit its text. Drag its edges on the waveform, or type new times, to fix the timing.
Step 3: Use Split, Merge, Shift and find & replace for bigger changes; undo is always one key away.
Step 4: Pick SRT, VTT or ASS and press Export.
Good to know
Formats
Combines several files into one result.
How it runs
- Built-in browser features
- Uses standard browser features only — nothing extra to download.
- Web Audio
- Audio is processed with the browser’s built-in Web Audio engine, sample-accurate and fast.
Subtitle editor, Subtitle Sync or Auto Captions: which one you need
Use the editor when individual lines are wrong. If every line is late by the same amount, a whole-file shift is faster, and if you have no subtitles at all, let speech recognition write a first draft.
| Your problem | Best tool | Why |
|---|---|---|
| Typos, wrong words, lines to split or join | Subtitle editor (this page) | Line-by-line text editing with the video beside it |
| A few lines start too early or too late | Subtitle editor | Drag each line’s edges on the waveform |
| Every line is off by the same delay | Subtitle Sync | One offset, applied to the whole file |
| Lines drift further out of sync over time | Subtitle Sync | Two-point or frame-rate correction |
| No subtitle file yet | Auto Captions | Writes a timed draft from the speech on your device |
How to create an SRT file from scratch
- Drop only the video. The editor opens with an empty list and the waveform of its audio.
- Play the video and press A (or Enter) where a sentence starts. A new line, up to two seconds long, appears at the playhead.
- Type the words, then press ] where the sentence ends to set the end time exactly.
- Repeat for each sentence, then export as SRT. Typing a whole film is slow; for long videos, generate a draft with Auto Captions and correct it here.
Keyboard shortcuts
| Key | What it does |
|---|---|
| Space | Play or pause |
| ← / → | Jump 1 s back or forward (Shift: 5 s) |
| ↑ / ↓ | Select the previous or next line |
| A or Enter | Add a line at the playhead |
| [ and ] | Set the selected line’s start or end to the playhead |
| S / M | Split the line at the playhead / merge it with the next one |
| Delete | Remove the selected line |
| Ctrl or ⌘ + Z | Undo (add Shift to redo) |
Readable timing: what the warnings mean
Each line shows its duration. An amber cps tag appears when a line asks viewers to read more than about 20 characters per second, and an Overlap tag when it starts before the previous line ends. Netflix’s English style guide uses the same scale: at most 20 characters per second for adult programmes and 42 characters per line.
Fix a fast line by lengthening it, splitting it in two or cutting words. Fix an overlap by pulling the earlier line’s end back.
Tips & troubleshooting
Every line out by the same amount? Click Shift and enter milliseconds; switch on “Only the selected line and after” to fix a late section.
Got
[MUSIC], speaker names or<i>tags you do not want? The SRT cleaner removes them from the whole file in one pass.Editing an ASS file? Export as ASS to keep its styles; lines you leave untouched keep their override tags exactly.
Done? Burn subtitles into video for social media, or add subtitles to video as a track viewers can switch off.
Subtitle Editor FAQ
How do I edit an SRT file?
Drop the .srt file here with its video, click a line and type. To change timing, drag the line’s edges on the waveform or edit the start and end times. When you are done, press Export to save a new SRT.
How do I edit SRT file timing?
For single lines, drag them on the waveform or press [ and ] while the video plays to set start and end. For the whole file, use Shift here or the subtitle sync tool, which also fixes drift that grows over time.
Can I edit subtitles without installing Subtitle Edit?
Yes. This editor runs in Chrome, Edge, Firefox or Safari on Windows, Mac, Linux and ChromeOS, with a waveform, video preview and undo, and nothing to install. Desktop editors still win for heavy jobs such as OCR of picture subtitles.
Which formats can I open and export?
It opens SRT, VTT, ASS, SSA, SBV, MicroDVD SUB, SAMI, LRC and TTML in any text encoding, and exports SRT, VTT or ASS in UTF-8.
Is your video uploaded anywhere?
No. Your video is processed by your own browser on your own device. There is no server that receives files, so nothing is uploaded, stored or shared. You can even switch to airplane mode once the page has loaded.