fixsubtitles is a free toolkit for working with subtitle files — converting between SRT, VTT and ASS, fixing timing and encoding, merging, splitting and editing. One principle shapes everything here: your files never leave your device. Every tool runs entirely in your browser, in JavaScript. There is no upload, no server that touches your files, and no account.
Why it works this way
A subtitle file often reveals exactly what you’re watching or working on — an unreleased cut, a client’s footage, a fan translation in progress. The usual subtitle sites make you upload that file to a stranger’s server just to change a comma to a period. That always felt backwards. Subtitle processing is simple enough to do locally, so it should be done locally. Building it client-side isn’t a feature bolted on for marketing — it’s the whole design, and it’s why the site can stay free with no file-size limits: there are no servers to pay for.
Who builds it
fixsubtitles is built and maintained by a solo developer. That means no support team and no roadmap committee — but also that the person reading your bug report is the person who fixes it. The tools are tested against a library of deliberately nasty real-world files: mojibake in a dozen encodings, broken numbering, framerate drift, three-hour films with thousands of cues, right-to-left and CJK scripts. When a conversion has to drop something it can’t represent, the tool tells you exactly what it changed rather than corrupting the file silently.
The reference behind the tools
The same care goes into explaining the formats. The guides are written as proper references — what an SRT file actually is, how WebVTT differs, why subtitles drift out of sync, and why non-English subtitles turn to gibberish. They’re the kind of pages you check when something breaks — accurate to the specs, with real examples.
How the site is funded
Free tools still have to pay for themselves, and being upfront about how is part of the deal. The honest breakdown — ads, the occasional relevant affiliate link, and what will never happen to your files — is on the how this site makes money page.
Got a broken file, a format edge case, or a tool you wish existed? The contact form is the way to reach me.