Free Online Subtitle Tools — Sync, Convert, Merge, Edit

Fix timing issues, convert between formats, combine tracks, and edit text — all free, all in your browser. No downloads, no signups, no data leaves your device.

Key Takeaways

Four free tools for every subtitle task: sync timing with millisecond precision, convert between SRT/VTT/ASS/SUB, merge multiple tracks into one, and edit text and timestamps visually. Everything runs client-side in your browser — your files stay on your device, no account needed, no limits.

Subtitle Sync Tool

Fix subtitle timing that is ahead or behind the audio. Shift all timestamps by a positive or negative millisecond offset, or let auto-detect find the correction for you.

  • Millisecond-precision offset controls
  • Auto-detect sync correction
  • Preview timestamps before downloading
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Subtitle Format Converter

Convert between SRT, VTT, ASS, and SUB formats instantly. Upload any supported subtitle file, choose your target format, and download the converted result in seconds.

  • Supports SRT, VTT, ASS, and SUB
  • Preserves styling and formatting tags
  • Batch convert multiple files at once
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Subtitle Merge Tool

Combine multiple subtitle tracks into a single file. Create bilingual subtitles, merge hearing-impaired tracks, or join split files with automatic timing alignment.

  • Merge two or more subtitle files
  • Automatic timing alignment
  • Color-coded multilingual output
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Subtitle Editor

Edit subtitle text and timing directly in your browser. Fix typos, adjust individual timestamps, add or remove lines, and preview changes in real time before downloading.

  • Visual timeline editor
  • Edit text and timestamps inline
  • Add, delete, and reorder subtitle lines
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Why Use Browser-Based Subtitle Tools?

Traditional subtitle software requires downloading, installing, and updating desktop applications. SoftSubs tools eliminate all of that friction. Open a tool, drag in your file, make your changes, and download the result — all within your web browser.

Complete Privacy

Every SoftSubs tool runs 100% client-side using JavaScript. Your subtitle files are processed locally on your device and never uploaded to any server. Close the tab, and all data is gone. There are no accounts, no cookies tracking your files, and no analytics on your content.

Works on Any Device

Because these tools run in the browser, they work on Windows, macOS, Linux, ChromeOS, iOS, and Android. No platform-specific installers, no compatibility issues. If your device has a modern browser, the tools will work.

Always Up to Date

No need to check for updates or reinstall. Every time you open a SoftSubs tool, you get the latest version automatically. New format support, bug fixes, and performance improvements are available instantly.

No Limits or Paywalls

There are no file size limits, no daily usage caps, and no premium tiers. Every feature of every tool is available to everyone, for free. We believe subtitle accessibility should not be behind a paywall.

Need More Than Editing?

SoftSubs is a complete subtitle platform. Find subtitles, translate them, or ask the community for help.

Find Subtitles

Browse 10M+ verified subtitles for movies, TV shows, YouTube, and podcasts. Quality-rated by our community in 200+ languages.

Explore Library

AI Translation

Translate any subtitle file into 200+ languages using AI with cultural localization. Community editors refine every result for accuracy.

Start Translating

Request Help

Can’t find the subtitles you need? Post a request and let our community of 500,000+ contributors help. Vote on requests to prioritize them.

Browse Requests

Frequently Asked Questions

Are these subtitle tools really free?

Yes, all SoftSubs subtitle tools are completely free to use. There are no hidden fees, no signup required, and no usage limits. Every tool runs entirely in your browser — your files never leave your device.

Do I need to install any software?

No. All SoftSubs tools are browser-based and work on any modern device — desktop, tablet, or phone. Just open the tool, upload your subtitle file, and start editing. No downloads or plugins required.

What subtitle formats are supported?

SoftSubs tools support SRT (SubRip), VTT (WebVTT), ASS (Advanced SubStation Alpha), and SUB (MicroDVD) formats. You can convert between any of these formats using the Format Converter tool.

How do I fix subtitles that are out of sync?

Use the Subtitle Sync Tool. Upload your subtitle file, enter a positive or negative millisecond offset to shift all timestamps, or use the auto-detect feature to let the tool find the correct offset automatically. Preview the corrected timestamps and download the fixed file.

Can I merge subtitles in different languages?

Yes. The Merge Tool lets you combine two or more subtitle tracks — even in different languages — into a single file. This is useful for creating bilingual subtitles or combining hearing-impaired and standard tracks.

Is my data private when using these tools?

Absolutely. All processing happens locally in your browser using JavaScript. Your subtitle files are never uploaded to any server. Once you close the tab, no trace of your files remains. There are no accounts, no tracking cookies on your content, and no server-side storage.