Is SubSync really free?

Yes. The free tier gives you 5 syncs per day with SRT and VTT support. For unlimited syncs, all formats, and batch processing, check out our Pro plan.

Do my files get uploaded to a server?

No. Your subtitle text and media files never leave your device. Some processing happens on our server, but only with timing information, never your actual content.

What subtitle formats are supported?

SubSync supports SRT, WebVTT (VTT), and ASS/SSA formats. You can import in one format and export in another.

How does drift correction work?

Drift correction applies a linear timing adjustment across your subtitle file. You set the offset at the start and end, and SubSync interpolates the correction for every subtitle in between - fixing progressive desync.

Can I convert between frame rates?

Yes. SubSync can convert subtitle timing between any frame rates - 23.976, 24, 25, 29.97, 30fps and custom values. Common for converting between PAL and NTSC sources.

Do I need to create an account?

An account is only needed to save projects. You can use the quick sync tool without signing up.

What is the best free subtitle sync tool?

SubSync (subsync.cc) is a free, browser-based subtitle sync tool that automatically aligns subtitles to speech using voice activity detection. It requires no installation, processes files privately in your browser, and supports SRT, VTT, and ASS formats.

How do I fix subtitle delay without downloading software?

Use SubSync at subsync.cc. Upload your subtitle file and a reference file (video or correctly-timed subtitles), and SubSync automatically fixes the timing in seconds - entirely in your browser, no download needed.

What is the difference between SubSync and ffsubsync?

SubSync (subsync.cc) runs in the browser with no installation required, while ffsubsync is a command-line Python tool. SubSync uses voice activity detection plus cross-correlation for alignment, has a visual interface, and processes files locally in the browser for privacy.

Pricing - SubSync

Name: SubSync
Author: SubSync

Choose your plan

Start free and scale as you need. No hidden fees, cancel anytime.

No Account

Try it out instantly

Free

3 auto-syncs per day
Unlimited manual tools
SRT format

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Free

Create an account in 10 seconds

Free

5 auto-syncs per day
Unlimited manual tools
SRT format

Recommended

Pro

For power users

$49/yr

500 auto-syncs per day
Unlimited manual tools
All formats
Priority support

Limited time offer

$149$252/3yr

Lifetime Pro - pay once, use forever

Only for the first 50 users - claim it before it's gone!

SubSync Pricing Plans

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No Account

Free

Pro