How do I combine two subtitle files into one?

Paste file A and file B into the two input boxes, choose a mode, and click Merge. In 'Sequential' mode B plays after A ends; in 'Overlay' mode both languages show together on the same timeline.

When should I use Overlay mode?

Overlay mode is for dual-language subtitles: each cue shows the line from file A above the line from file B, aligned by their original timings. Both files should cover the same video.

Is my subtitle file uploaded anywhere?

No. Merging happens locally in your browser with JavaScript. Your files never leave your device.

Merge Subtitles — Join Two Subtitle Files

Combine two subtitle files — sequential join or dual-language overlay. Instantly, right in your browser.

Two merge modes

Sequential — for two-part subtitle files (CD1 + CD2, part 1 + part 2). File B's first cue is moved to just after file A's last cue ends, so playback is continuous. Overlap inside either file is preserved as-is.
Overlay — for bilingual subtitles. Both files are laid on one timeline; wherever they cover the same moment, the cue shows file A's lines on top and file B's lines underneath. The union of both files' cue boundaries defines the new timing grid, so nothing is lost.

Typical use cases

Join movie-1.srt and movie-2.srt from a two-disc release into one file
Build dual-language subtitles from an English original and a translation
Combine a dialogue track with a comment/annotation track for study videos

If the merged result plays slightly early or late, fix it afterwards with Shift Subtitles. Want the output in WebVTT instead? Run the result through SRT to VTT.

Merge Subtitles

Two merge modes

Typical use cases

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