Video Merger
Combine multiple videos into a single MP4 — entirely in your browser. No upload, no account.
Drop your video files here
or click to select files
Up to 5 videos · Max 200 MB each · Files never leave your device
Merge Videos in Your Browser — No Upload Required
Combine multiple video files into a single MP4 entirely in your browser. Drag to reorder, then download.
Everything You Need to Merge Videos
From drag-and-drop upload to one-click download — no server, no waiting.
Drag-to-Reorder
Arrange your video clips in any order before merging.
Drag the handle next to each file to reorder. Touch devices supported.
Smart Compatibility Check
We detect codec and resolution mismatches before merging.
If clips don't match, we re-encode them to a single MP4 so the result always plays.
MP4 Output
Downloads a clean MP4 (H.264 + AAC) that plays everywhere.
No watermarks, no metadata, no proprietary container.
Up to 5 Videos
Combine up to 5 video files in a single merge operation.
Each file can be up to 200 MB. Run the tool again for more.
Zero Upload
Merging happens entirely in your browser using FFmpeg.wasm.
Files are never sent to any server.
Instant Download
The merged video downloads directly to your device.
No cloud storage, no email — straight to your downloads folder.
Inside the pipeline
How to Merge Video Files
Upload your videos
Drop up to 5 video files into the upload area or click to select them from your device.
Reorder if needed
Drag the files into your desired merge order. The merged video will follow this sequence.
Click Merge Videos
Wait while FFmpeg.wasm combines your clips into a single MP4 — entirely in your browser.
Download the result
Click Download to save merged-video.mp4 directly to your device.
Why MacroKit Video Merger?
Built for privacy-first video workflows.
Zero Upload
Your videos never leave your device. Merging happens entirely in your browser using FFmpeg.wasm.
No Queue
No waiting for server-side processing. Merge starts the moment you click the button.
No Account
No signup, no email, no subscription. Open the tool and start merging immediately.
No Watermarks
Your merged MP4 is clean. No branding, no watermarks, no hidden metadata added.
Works Offline
Once the page loads, you can merge videos without an internet connection.
Universal MP4 Output
Output is H.264 + AAC inside MP4 — playable on every modern device and browser.
How Video Merging Works
MacroKit uses FFmpeg.wasm — a WebAssembly port of FFmpeg — to combine your videos directly in your browser. Each file is loaded into the in-memory file system, concatenated, and re-encoded to a single MP4 that downloads to your device.
▸ All processing happens in your browser tab. Closing the tab cancels any in-progress merge.
If your clips share the same codec and resolution, the merge is fast. If not, the tool transparently re-encodes everything to a uniform MP4 (1280×720, H.264, AAC) so the output always plays — at the cost of a slightly longer merge.
MacroKit vs Other Video Mergers
See how browser-based merging compares to typical online tools.
Frequently Asked Questions
Is this video merger really free?+
Are my videos uploaded to a server?+
How many videos can I merge at once?+
Which input formats are supported?+
What if my videos have different resolutions or codecs?+
Why is the output MP4 instead of my original format?+
Can I merge very large videos?+
Does this work on mobile?+
More Free Tools
Privacy & Security
MacroKit Video Merger runs entirely in your browser using FFmpeg.wasm. No video data is transmitted to any server. Files are read from your local device and the merged result downloads directly to your device.
Ready to merge your videos?
Drop your files above and get a single MP4 in seconds — no account, no upload.