About delsub
In short: delsub is a free, single-purpose tool that turns subtitle files into readable text. It is designed, built and maintained by one person, Claudio Cárdenas, and it runs entirely in your browser: your subtitles are never uploaded by the tool.
Why it exists
Subtitle files are full of things a reader doesn’t need: cue numbers, timestamps, formatting tags, sound annotations and, in automatic captions, the same sentence repeated two or three times. Cleaning that up by hand, or with a long find-and-replace session, can take longer than watching the video.
delsub does it in one step. You paste text or drop a .srt, .vtt or .sbv file, and you get continuous, paragraph-formatted text you can quote, summarize, translate, publish or hand to a language model.
How it works
The page loads a small JavaScript program. When you paste text or drop a file, the text-processing code reads and rewrites it inside your browser tab without uploading it or storing a server copy. Its own preference code remembers your cleaning options in your browser’s local storage.
Each step is an independent rule you can switch off — timestamps, sequence numbers, tags, sound cues, roll-up repeats — and the paragraph rebuilder joins caption lines into sentences using their punctuation. The guides explain what each rule does, with examples, and where its limits are.
What delsub doesn’t do
- It doesn’t transcribe audio or video. It works on subtitle text that already exists.
- It doesn’t download subtitles from websites. You bring the file or the text.
- It doesn’t correct recognition errors. If automatic captions misheard a word, the clean text contains the same word.
- It doesn’t translate. The output is in the language of the subtitles.
How it is built
The cleaning rules are covered by an automated test suite, built on examples of each format — including YouTube’s automatic captions — that runs before every release. When a bug is fixed, a test that reproduces it is added so it cannot come back unnoticed.
The site is designed to be usable with a keyboard and a screen reader, and its text meets the WCAG AAA contrast level (7:1) in both the light and dark themes. Contrast is checked automatically against the real stylesheet, so a change that lowers it stops the release.
Who makes it
delsub is made by Claudio Cárdenas, a software developer. It is part of a small family of browser-only tools that share the same principles: one job, done locally, without accounts. Its sibling is delexif, which removes location and camera data from photos. More about the author is at claudiocardenas.dev, and you can write to him at contact@claudiocardenas.dev; the Contact page explains what to include.
How the site is funded
delsub is free and has no accounts, subscriptions or paid tiers. Google AdSense units and a European consent message are configured for the home page and individual guides. Advertising is currently disabled while the consent integration is verified; any later ad display also depends on Google’s site approval, availability and applicable consent choices. We measure aggregate visits with Cloudflare Web Analytics. The text-processing code does not send your subtitles to those services, and advertising scripts, if enabled, run in the same page as the tool. The Privacy Policy explains visit data, cookies and Google’s European consent controls; the rules for using the site are in the Terms of Use.