Best free subtitle tools for SRT, VTT, ASS & caption files
The right subtitle tool depends on your workflow. This guide covers the best tools by category: existing-file manipulation, AI subtitle generation, desktop editing, and transcription services.
The most important distinction: do you have a subtitle file already?
I need subtitles created from video/audio
- VEED — AI subtitle generation, video editor
- Kapwing — AI captions, translation, social video
- Flixier — AI subtitles in 130+ languages
- Happy Scribe — AI + human-reviewed transcription
I already have a subtitle file
- SubtitleTools.space — convert, fix, sync, edit, browser-local
- GoTranscript converter — many formats including STL, SCC
- SubtitleTools.com — established, ad-free utility site
- Subtitle Edit — desktop, advanced, 300+ formats
Best tools for existing subtitle files
1. SubtitleTools.space — Browser-local subtitle file toolkit
Best for: Converting SRT/VTT/ASS, fixing timestamps, shifting timing, editing text, stripping formatting — all in the browser with no upload.
- SRT ↔ VTT ↔ ASS conversion, SRT to TXT, YouTube transcript to SRT
- Fix broken timestamps, numbering, and overlapping cues
- Shift subtitle timing by fixed offset
- FPS timing conversion (23.976 ↔ 25 ↔ 29.97 etc.)
- Strip HTML and hearing-impaired tags from SRT
- Online SRT editor for text changes
- 100% browser-local — files never leave your device
2. GoTranscript Subtitle Converter
Best for: Wide format coverage including STL, SCC, DFXP, SMI, CSV, SUB — formats not yet on SubtitleTools.space.
- Free, no account needed
- Most comprehensive format list of any free browser converter
GoTranscript converter alternative →
3. SubtitleTools.com
Best for: Users who want an established, ad-free subtitle utility site with no third-party tracking.
- Established site, broad tool coverage
- Explicitly ad-free and no third-party tracking cookies
SubtitleTools.com alternative →
4. Subtitle Edit (desktop)
Best for: Power users who need a full desktop subtitle editor with 300+ formats, audio waveform sync, OCR, batch processing, and spell check.
- Free, open-source (Windows; Wine needed for Mac/Linux)
- The most capable free subtitle editor available
- No browser required; works offline
Subtitle Edit online alternative →
5. Aegisub (desktop)
Best for: Advanced ASS subtitle editing — karaoke timing, anime typesetting, audio synchronization, complex styles.
- Free, open-source, cross-platform
- Industry standard for anime fansub and ASS subtitle work
6. Ebby subtitle converter
Best for: Very simple browser-based format conversion (SRT ↔ VTT).
Best tools for AI subtitle generation
1. VEED — online video editor with AI subtitles
Upload a video, auto-generate captions, style them, and export the captioned video or an SRT/VTT file. Strong creator/social content focus.
2. Kapwing — collaborative AI caption platform
Auto-generates and translates subtitles, free tier includes up to 10 minutes of subtitles, integrates with team workflows.
3. Flixier — AI video editor with 130+ language subtitles
Cloud-based video editor with fast AI subtitle generation and auto-translation.
4. Happy Scribe — transcription + human review
Best for professional-grade subtitles from audio/video, with optional human review for accuracy.
Full comparison matrix
| Tool | AI gen from video | SRT/VTT convert | Repair tools | No account | Browser-local | Free tier |
|---|---|---|---|---|---|---|
| SubtitleTools.space | ❌ | ✅ | ✅ | ✅ | ✅ | ✅ All tools |
| GoTranscript converter | ❌ | ✅ Many formats | Limited | ✅ | Uploads file | ✅ |
| SubtitleTools.com | ❌ | ✅ | ✅ | ✅ | Check policy | ✅ |
| Subtitle Edit | ❌ | ✅ 300+ formats | ✅ | ✅ | ✅ Desktop | ✅ |
| Aegisub | ❌ | ✅ | ✅ | ✅ | ✅ Desktop | ✅ |
| VEED | ✅ | Via project | Limited | Account required | Video uploaded | Limited free |
| Kapwing | ✅ | Via project | Limited | Account required | Video uploaded | 10 min / watermark |
| Flixier | ✅ | Via project | Limited | Account required | Cloud | Limited |
| Happy Scribe | ✅ + human | On export | Limited | Account required | Media uploaded | Per-minute cost |
Which tool should you choose?
- For converting or fixing existing SRT/VTT files: SubtitleTools.space (browser-local, no account)
- For rare format like STL, SCC, DFXP: GoTranscript free converter
- For full desktop subtitle editing on Windows: Subtitle Edit
- For advanced ASS typesetting/karaoke: Aegisub
- For AI captions from video (creator workflow): VEED or Kapwing
- For professional transcription + human review: Happy Scribe
Frequently asked questions
What is the best free subtitle converter?
For browser use: SubtitleTools.space (SRT, VTT, ASS, SBV, LRC) and GoTranscript (more formats including STL, SCC, DFXP). For desktop batch conversion: Subtitle Edit (300+ formats).
What is the best free subtitle editor?
Desktop: Subtitle Edit (Windows) and Aegisub (all platforms, ASS). Online: SubtitleTools.space SRT Editor.
What subtitle tool is best for YouTube?
For generating from video: VEED or Kapwing. For converting/fixing existing files for YouTube upload: SubtitleTools.space (SRT, VTT, SBV support).