Who runs this site
Subtitle.tools (subtitle.tools) is operated by Anderson Gomes Ferreira. contato@subtitle.tools
How it works
SRT, WebVTT, ASS/SSA and YouTube SBV are read and written by code in your browser. Times are kept to the millisecond; ASS keeps its styles, actors and override tags when you save back to ASS, and drops the override tags when you save to a format that cannot show them.
Shifting adds the same offset to every line, or to every line from a point on. Two-point sync takes two lines whose correct times you know and stretches the whole file between them, which fixes a delay and a drift together. A frame-rate change scales every time by the ratio of the two rates.
Checks count the characters a viewer reads (no tags, no line breaks) and divide by the time on screen. The limits are yours to set; the presets are the numbers Netflix publishes for English subtitles, linked where they appear.
Files are read with the File API and never uploaded. A video you load for preview plays from your own disk through a local address that only this tab can use.
Where the data and rules come from
- Netflix: English (USA) Timed Text Style Guide — 42 characters per line, two lines, 20 or 17 characters per second
- Netflix: Timed Text Style Guide, General Requirements — Minimum 5/6 of a second, maximum 7 seconds
- Netflix: Subtitle Timing Guidelines — Minimum gap of 2 frames
- W3C: WebVTT, The Web Video Text Tracks Format — WebVTT file and timestamp syntax
- Aegisub: ASS Override Tags — Italic, bold, underline, line breaks and alignment in ASS
- YouTube Help: Supported subtitle and closed caption files — SBV and the formats YouTube accepts
How we keep the content up to date
Each style number shows the page it comes from and the day we opened it. They are checked again when the publisher changes its guide.
What this site is not
This site edits subtitles; it does not make them from audio. For that, transcribe.tools turns speech into an SRT or VTT file on your device. Style limits differ between broadcasters, languages and clients: the presets are one published guide, not a universal rule.
Get in touch
Found a mistake, have a question or a suggestion? See the channels on the contact.
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