**Subtitle Editor Online — Edit SRT, VTT, ASS Free | SozAI** Source: https://sozai.app/tools/subtitle-editor/ Free tool # Subtitle Editor Open a subtitle file, fix the text and timings against your video, and download it again. No install, no upload — the file and the video stay on your device. - Runs in your browser - Nothing uploaded - No signup Open a subtitle file SRT, VTT, SBV or ASS — drop it here or tap to choose. The format is read from the content. Paste subtitles instead Subtitle text (SRT, VTT, SBV or ASS) How it works ## Subtitle Editor in three steps 01 ### Open your subtitles Drop an SRT, VTT, SBV or ASS file, paste the text, or start from scratch. 02 ### Edit text and timing Fix cues inline, shift, split or merge them, and play your video with the subtitles over it. 03 ### Download the result Clear the flagged problems and export to SRT, VTT or plain text. ## What the editor does Open a subtitle file and every cue becomes a row: number, start, end and text, all editable in place. The format is read from the content, not the file name, so a renamed SBV or an SRT saved as .txt opens correctly. SubRip (.srt), WebVTT (.vtt), YouTube's SBV and Advanced SubStation Alpha (.ass and .ssa) are supported. Timecodes accept what people actually type: `00:01:02,500`, `1:02.5` or just `62.5` seconds. A value that is not a timecode is marked red and not applied, so a typo never corrupts the file. - **Shift** moves every cue, or only the selected ones, by any number of seconds forward or back. A cue that would start before 0:00 is stopped at 0:00 and the page tells you how many were. - **Split** cuts a cue where your cursor is, or at the line break or space nearest the middle, and divides its time in proportion to the characters on each side. - **Merge** joins two or more cues in a row: the start of the first, the end of the last, the text on separate lines. - **Add**, **Delete** and **Undo** (the last 60 actions) do what they say. ## Timing against your video Add a video or audio file and it plays right on the page with the current cue drawn over the picture, while the matching row lights up in the list. Click a cue number to jump there; "Start here" and "End here" set the selected cue's times to the playhead. The video is played from your own device and never uploaded — any file your browser can play works, MP4 with H.264 everywhere. ## Which checks run, and on what numbers? Every change is checked at once, and each problem is flagged on its row with a count at the top that jumps to the next one: - **Overlap** — a cue starts before the previous one ends. "Fix overlaps" ends each earlier cue where the next begins. - **Ends before it starts** — the end time is not after the start time. - **Too fast to read** — the cue has more characters per second than the limit you choose: 15, 17, 20 or 25 (17 by default), or off. Characters include spaces but not line breaks or formatting tags. - **Line too long** — a line has more characters than your limit: 32, 37 or 42 (42 by default), or off. - **Empty** — a cue with no text. | Limit, characters per second | Characters in a 2-second cue | Characters in a 4-second cue | | --- | --- | --- | | 15 | 30 | 60 | | 17 | 34 | 68 | | 20 | 40 | 80 | | 25 | 50 | 100 | There is no single correct number: subtitle guidelines differ by platform, broadcaster and audience, and are usually stricter for children's content than for adults. Use the limit your client or platform asks for. ## Saving and exporting Your working file is saved in this browser after every change, so a closed tab or a crash does not lose the edits — open the page again and it is back. Nothing is uploaded; the copy lives only in this browser, and "Close file" deletes it. Download as SRT, as WebVTT, or as plain text with one cue per line. SRT is renumbered from 1 and written with millisecond timecodes. Some things do not survive the trip through the editor: ASS styling and positioning tags and WebVTT cue settings and notes are dropped on import, because SRT has no place for them. Italic tags like `` are kept as text. Answers ## Subtitle editor — frequently asked questions Which subtitle formats can I open? SRT, WebVTT (.vtt), YouTube SBV and ASS/SSA. The format is detected from the content, so the file extension does not matter. You can also paste subtitle text instead of opening a file. Is my video uploaded? No. The video or audio plays from your own device through the browser; it is never sent anywhere. The subtitle file is not uploaded either — it is only saved in this browser so your edits survive a closed tab. How do I fix subtitles that are out of sync? If every cue is early or late by the same amount, type the difference in seconds into Shift by — for example 1.5 or -0.75 — and press Shift. If only part of the file drifts, select those cues first and shift only the selection. What is a good reading speed for subtitles? Reading speed is the number of characters on screen divided by the seconds the cue is shown. Published guidelines mostly sit between 15 and 20 characters per second for adult viewers and lower for children. The editor lets you pick 15, 17, 20 or 25 and flags every cue above it. Can I convert between formats here? Yes: open any supported format and download SRT, VTT or plain text. Styling from ASS files and WebVTT positioning are not carried over, because SRT cannot hold them. What happens if I close the tab? Nothing is lost. The working file is saved in this browser after every change and comes back when you open the page again. It is stored only on this device; Close file deletes it. Can the editor make subtitles from a video? No, it edits subtitles that already exist. To create them from speech, use the subtitle generator first and then fine-tune the result here. Need Full Transcription? Upload audio or paste a YouTube link and get a full AI transcript with speaker labels, timestamps, and summaries. [Get the App — Free](https://sozai.app/download/) Free on iOS and Android. No account required. Free tools ## More Free Tools - [01 ASS to SRT Converter](https://sozai.app/tools/ass-to-srt/) - [02 Merge SRT Files](https://sozai.app/tools/merge-srt/) - [03 SBV to SRT Converter](https://sozai.app/tools/sbv-to-srt/) - [04 SRT to TXT Converter](https://sozai.app/tools/srt-to-txt/) - [05 SRT to VTT Converter](https://sozai.app/tools/srt-to-vtt/) - [06 SRT to Word Converter](https://sozai.app/tools/srt-to-docx/) - [07 SRT Validator](https://sozai.app/tools/srt-validator/) [YouTube Transcript Generator](https://sozai.app/youtube-transcript/) · [SozAI vs Other Tools](https://sozai.app/compare/) · [Alternatives to Popular Apps](https://sozai.app/alternatives/) --- This is the markdown twin of https://sozai.app/tools/subtitle-editor/ — the same content, without the markup. Published by SozAI (https://sozai.app). Reuse and quotation are allowed with attribution and a link back. Machine-readable index: https://sozai.app/llms.txt · data API: https://sozai.app/api/