~/tools/video-merge

Merge Videos

Join multiple videos in order, right in your browser. Your files never leave your device.

-f concat -c copy
Engine:ffmpeg.wasmWaiting to initialize…

$Drop multiple video files here, or click to select

Batch selection supported; at least 2 video files required.

Files never leave your device
MP4MOVMKVAVIWebM
01Drop your files

Load files into browser memory in order; nothing is uploaded.

02Arrange & export

Drag to reorder clips and pick the output container format.

03Download locally

FFmpeg WASM concatenates and exports everything locally.

//Related Video ToolsAll tools

Merge Videos Online

Local · No uploads

Combine multiple videos into one file, in the order you choose. Upload in batches and rearrange by dragging. Clips with different resolutions or encodings are automatically transcoded to a uniform output — great for stitching together footage or building compilations. Everything is processed locally in your browser.

How to Merge Videos

  1. 1

    Upload multiple video files

  2. 2

    Arrange the merge order — drag to reorder

  3. 3

    Choose the output format

  4. 4

    Click Merge, then download the combined video

Common Uses

  • Stitch multiple clips into one complete video
  • Organize footage shot at different times
  • Build compilations or continuous content

Things to Keep in Mind

  • Videos with different resolutions or encodings are re-encoded to a uniform output
  • Clips with very different frame rates or audio tracks may drift slightly out of sync
  • Merging several large files takes time and browser memory

How to Choose a Video Merger

  • vs. professional editors: focused on merging only — zero learning curve
  • vs. upload-based tools: nothing is uploaded, so it's private
  • Supports batch upload and reordering for multi-clip joins in one pass

Two Ways to Join Videos

  • The lossless path is concat stream copy: when clips share the exact same codec, resolution, and frame rate, they're joined end to end without re-compressing — fast and zero quality loss.
  • Clips with mismatched parameters must be re-encoded to a common spec — every segment is compressed to the same settings before being joined. That's also the more robust route for mixed footage.
  • Audio-video desync usually traces back to differing timebases or frame rates between clips; transcoding everything to one spec eliminates most of it.

Video Merging FAQ

What happens with videos of different resolutions?

They're transcoded and merged into one uniform output. For best results, merge clips that share the same resolution.

How many videos can I merge?

There's no fixed limit — it depends on the total file size your browser's memory can hold.

Does merging reduce quality?

Merging re-encodes the video. Default settings stay close to the original; when source clips differ significantly, they're normalized to a uniform spec.

Can I change the order of the videos?

Yes. After uploading, drag to reorder the list — that determines the final sequence.

Can I combine multiple clips into a single file?

Yes. Upload them, arrange the order, and merge everything into one complete video in a click.