Subtitle Kit

Subtitle Kit helps creators and localization freelancers fix common subtitle problems in the browser. Use the SRT time shift tool when every line is consistently early or late—adjust by seconds or milliseconds and download a corrected file. Convert SRT to plain text when you need dialogue without timing codes for translators or script review. The caption line length checker flags lines that are too long for 9:16 short-form video. The read-time estimator plans narration length using adjustable words-per-minute presets. All processing happens on your device; we do not upload your subtitle files for server-side conversion. The site is free, fast, and designed for privacy-conscious workflows on Cloudflare Pages. Ideal for dubbing sync tweaks, translation prep, and social caption readability—not a replacement for full NLE suites, but a quick online helper when you need results in minutes.

What problem it solves

Video editors and translators often get an .srt that is consistently early or late after dubbing or re-export, need dialogue without timecodes for translation, or need to check whether lines are too long for TikTok/Reels. Desktop apps and upload-based converters are slow or send subtitle files to a server. Subtitle Kit fixes these jobs in the browser: shift timing, export plain text, check line length, and estimate read time—with processing on your device and no account.

Alternatives & competitors

Alternatives include desktop editors (e.g. Aegisub), NLE subtitle tracks, and online SRT tools that upload files to convert or shift timing. Subtitle Kit is a lighter option: free, browser-only, no upload for processing, built for quick sync tweaks and translation prep rather than full timeline editing.