How does bilingual mode align cues?

Bilingual mode finds cues with overlapping time ranges between the two files. For each primary cue, it identifies the secondary cue(s) that share the same timing window and combines their text. Non-overlapping cues are included individually.

Can I control which file's cues appear first in bilingual mode?

Yes. The order setting lets you choose whether the primary file's text appears first or the secondary file's text appears first within each combined cue. This determines the reading order for bilingual display.

What happens when cues overlap partially in bilingual mode?

When cues from the two files partially overlap in time, the merger creates combined cues for the overlapping portion and individual cues for non-overlapping portions. This preserves all subtitle content while maintaining timing accuracy.

Does the merger renumber SRT cues automatically?

Yes. In both modes, the output SRT file has cues renumbered sequentially starting from 1. This ensures valid SRT structure regardless of how the input files were numbered.

Can I merge more than two subtitle files?

This tool merges two files at a time. For three or more files, merge the first two, then use the output as input for the next merge. Repeat until all files are combined.

What output format should I choose?

SRT is the most compatible output format. VTT is preferred for web video and browsers. ASS preserves more styling but is less universally supported. Choose based on your target playback platform.

Absolutely. All processing happens client-side in your browser. No subtitle files are ever uploaded to a server.

How does the merger handle different frame rates between files?

The merger works with millisecond timestamps internally, so files with different frame rates can be merged. Timestamps are preserved as-is from each input file, maintaining their original precision.

Can I merge subtitle files from different video releases?

You can, but results may be poor if the timing differs significantly between releases. For best results, ensure both subtitle files are from the same video version. Sequential mode is more tolerant of timing differences than bilingual mode.

Does the merger support RTL (right-to-left) languages?

Yes. The merger preserves UTF-8 encoding and text content. RTL languages like Arabic and Hebrew display correctly in the output. Note that cue display direction depends on your video player's settings.

What if both files have exactly the same content?

In bilingual mode, you would get duplicate text per cue (original + identical copy). In sequential mode, you would get the subtitles played twice in sequence. This is unusual but technically valid output.

Can I use the merged file for DVD or Blu-ray authoring?

The merged output is a standard subtitle file. For DVD or Blu-ray authoring, you may need to convert it to the appropriate format (VOBSUB for DVD, PGS for Blu-ray) using your authoring software.

How large is the merged file?

The merged file is roughly the sum of both input files' sizes. In bilingual mode, it may be slightly larger due to combined cue text. In sequential mode, it is approximately the sum of both files since all cues from both are preserved.

Subtitle Merger

Fast. Private. Perfect.

Combine two subtitle files into one bilingual subtitle or merge them end-to-end. Perfect for dual-language subtitles and episode combining.

Private & Secure

Blazing Fast

Free & Unlimited

Track A

Hello, world!

Nice to meet you.

Track B

你好，世界！

很高兴认识你。

Merged

Hello, world!
你好，世界！
Nice to meet you.

Drag & drop your subtitle file here

or click to browse

SRT, VTT, ASS, SSA, LRC, SBV, TTML, SCC, STL, SMI, TXT

100% LocalNo UploadSecureInstant

How It Works

Select your first subtitle file (primary track).

Select your second subtitle file (secondary track).

Choose merge mode: bilingual (both languages visible per cue) or sequential (append second after first).

For bilingual mode, choose cue order and delimiter. For sequential mode, choose gap behavior.

The merger processes both files, aligning or concatenating cues based on your selected mode.

Download the combined subtitle file with properly renumbered cues and valid timing structure.

Why Choose AllSubConverter?

Your Privacy Matters

Everything runs in your browser. Your files are never uploaded.

Lightning Fast

Optimized processing engine converts files in seconds.

Truly Unlimited

No file size limits. No daily limits. Completely free.

Works Everywhere

Works on Windows, Mac, Linux, iOS, Android - any modern browser.

Key Features

Combine two subtitle files into one in bilingual mode (dual-language) or sequential mode (append)

Bilingual mode aligns cues by overlapping time ranges for side-by-side language display

Sequential mode concatenates files with an automatic timecode offset for continuous playback

Control gap behavior between sequential cues: no gap, blank line, or custom separator

Supports SRT, VTT, ASS, SSA, LRC, and SBV input formats in any combination

Flexible cue ordering: primary file first or secondary file first in bilingual output

Automatic re-numbering of sequential cues for valid output structure

100% client-side processing, no uploads, complete privacy

Common Use Cases

Multi-Part Video Subtitles

Combine subtitle files from a multi-part video (Part 1 and Part 2) into a single continuous subtitle file using sequential mode with automatic timecode offset.

Bilingual Display

Merge original and translated subtitle tracks into a single bilingual file using bilingual mode, showing both languages per cue for viewers who need both.

Split Video Reassembly

If a video was split into segments for editing, merge the individual subtitle files back into one continuous file for the reassembled video.

Subtitle Track Combination

Combine a regular subtitle track with an SDH (Subtitles for Deaf and Hard of Hearing) track, or merge primary dialogue with secondary commentary subtitles.

Episode Compilation

Merge subtitle files from TV episodes into a single file for a compilation or marathon cut, with proper sequential timing offsets for each episode.

Frequently Asked Questions

What is the difference between bilingual and sequential merge modes?

Bilingual mode aligns cues from both files by timestamp, displaying both languages simultaneously per cue. Sequential mode appends the second file's cues after the first file's cues, creating one continuous timeline. Use bilingual for dual-language display, sequential for combining multi-part videos.

Can I merge subtitles from different video parts?

Yes. Sequential mode is designed for this. Load Part 1 subtitles as the primary file and Part 2 subtitles as the secondary file. The merger offsets Part 2 timestamps to continue after Part 1 ends, producing a single combined subtitle file.

Which input formats are supported?

Both files can be in SRT, VTT, ASS, SSA, LRC, or SBV format. You can mix formats (e.g., SRT primary with VTT secondary). The output format is independent of the input formats.

How does sequential mode handle timecode offsets?

When appending the second file, sequential mode calculates the timecode offset based on the last cue in the first file. It adds the duration of the first file to all timestamps in the second file, so cues appear in the correct chronological order in the combined output.

What gap options are available in sequential mode?

You can choose no gap (cues flow continuously), blank line (a visual separator between the two files' cues), or custom separator (a text marker like --- between sections). This helps identify where the second file's content begins.

Is the subtitle merger free?

Yes, completely free with no sign-up, no watermarks, and no file size limits. All processing happens in your browser.

Ready to convert your subtitles?

Combine two subtitle files into one bilingual subtitle or merge them end-to-end. Perfect for dual-language subtitles and episode combining.