Free Subtitle & Caption
Tools in Your Browser
Convert, fix, and edit SRT, VTT, and ASS subtitle files without uploading a single file. Every tool runs locally — fast, private, and free forever.
Free Online Subtitle Tools — No Upload, No Server
SubtitleTools.space is a free collection of subtitle and caption utilities built for video creators, educators, accessibility teams, and anyone who works with subtitle files. Every tool runs entirely in your browser using JavaScript — your files never leave your device, there are no size limits imposed by a server, and processing is instant.
Whether you need to convert an SRT file to VTT for an HTML5 video player, fix out-of-sync subtitles from a 23.976 fps rip, repair broken numbering in an SRT file, or extract a clean text transcript from a subtitle file — you can do it all here in seconds, for free.
Looking for audio tools? Visit our sister site audiotools.space for free browser-based audio editing — trim, merge, convert, normalize, and edit audio without uploading.
What You Can Do with SubtitleTools.space
- Convert SRT to VTT online — transform SubRip files to WebVTT for use with HTML5 <video> and <track> elements.
- Convert VTT to SRT — bring WebVTT captions back to SRT for editing in Premiere, DaVinci Resolve, or other tools.
- Extract text from SRT — get a clean plain-text transcript by stripping all timing data and entry numbers.
- Fix subtitle timing/delay — shift all timestamps forward or backward to sync subtitles with a video.
- Convert subtitle FPS — rescale subtitle timing when the video frame rate differs from the subtitle source.
- Repair broken SRT files — renumber entries, strip HTML tags, remove hearing-impaired labels, and fix overlapping timestamps.
- Edit SRT files online — open, edit, and save SRT files directly in the browser with a live subtitle preview.
- Convert YouTube transcript to SRT — paste a copied YouTube transcript and get a properly timed SRT file.
- Convert SRT to ASS — generate Advanced SubStation Alpha files with custom font, colour, and positioning.
Frequently Asked Questions
Do my subtitle files get sent to a server?
No. All subtitle processing happens locally in your browser using JavaScript. Your files are never uploaded to any server and never leave your device.
Is SubtitleTools.space free?
Yes, all tools are completely free to use with no signup, account, or payment required.
What subtitle formats are supported?
Currently SRT (SubRip), VTT (WebVTT), ASS/SSA (Advanced SubStation Alpha), plain text transcripts, and YouTube transcript format. More formats will be added.
What is the difference between SRT and VTT?
SRT (SubRip Text) is the most widely supported format, using comma-separated millisecond timestamps (00:00:01,000). VTT (WebVTT) is the standard for HTML5 video, using dot-separated timestamps (00:00:01.000) and a "WEBVTT" header. Learn more in our SRT vs VTT guide.
My subtitles are out of sync — how do I fix them?
Use the Subtitle Delay Fixer to shift all timestamps forward or backward by a set number of milliseconds. If the sync issue worsens over time, the problem may be a frame-rate mismatch — use the FPS Converter instead.
Is there a file size limit?
No server-side limit. Since all processing runs in your browser, the limit is your device's available memory — typically many megabytes, far exceeding any typical subtitle file.