MacroKitMacroKit

Video Merger

Combine multiple videos into a single MP4 — entirely in your browser. No upload, no account.

100% Private
FFmpeg.wasm
No Upload
No Account

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.

Merge Videos Free
Features

Everything You Need to Merge Videos

From drag-and-drop upload to one-click download — no server, no waiting.

01

Drag-to-Reorder

Arrange your video clips in any order before merging.

Drag the handle next to each file to reorder. Touch devices supported.

02

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.

03

MP4 Output

Downloads a clean MP4 (H.264 + AAC) that plays everywhere.

No watermarks, no metadata, no proprietary container.

04

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.

05

Zero Upload

Merging happens entirely in your browser using FFmpeg.wasm.

Files are never sent to any server.

06

Instant Download

The merged video downloads directly to your device.

No cloud storage, no email — straight to your downloads folder.

How It Works

How to Merge Video Files

01

Upload your videos

Drop up to 5 video files into the upload area or click to select them from your device.

0101

Upload your videos

Drop up to 5 video files into the upload area or click to select them from your device.

02

Reorder if needed

Drag the files into your desired merge order. The merged video will follow this sequence.

0202

Reorder if needed

Drag the files into your desired merge order. The merged video will follow this sequence.

03

Click Merge Videos

Wait while FFmpeg.wasm combines your clips into a single MP4 — entirely in your browser.

0303

Click Merge Videos

Wait while FFmpeg.wasm combines your clips into a single MP4 — entirely in your browser.

04

Download the result

Click Download to save merged-video.mp4 directly to your device.

0404

Download the result

Click Download to save merged-video.mp4 directly to your device.

Benefits

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.

Technical Specs

How Video Merging Works

macrokit-specs
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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.

Specifications
EngineFFmpeg.wasm 0.12.10
Max files per merge5
Max size per file200 MB
Output formatMP4 (H.264 + AAC)
Output resolution1280×720
Upload requiredNever
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Comparison

MacroKit vs Other Video Mergers

See how browser-based merging compares to typical online tools.

MacroKit
VS
Others
Files uploaded to server
Files uploaded to server
Files uploaded to server
Account required
Account required
Account required
Watermark on output
Watermark on output
Watermark on output
Works offline
Works offline
Works offline
Drag-to-reorder
Drag-to-reorder
Drag-to-reorder
MP4 output
MP4 output
MP4 output
Free to use
Free to use
Free to use
FAQ

Frequently Asked Questions

Yes, completely free with no hidden costs, watermarks, or file limits beyond what your browser can handle. No account required.
No. All merging happens locally in your browser using FFmpeg.wasm. Your files never leave your device.
Up to 5 video files per merge, with a 200 MB limit per file. Run the tool again to combine more.
MP4, MOV, MKV, WebM, AVI, WMV, FLV, 3GP, MPG, and OGV. The output is always MP4 (H.264 + AAC) for maximum compatibility.
The tool detects mismatches and automatically re-encodes everything to a uniform MP4 (1280×720). This takes longer but guarantees a playable result.
MP4 (H.264 + AAC) plays on virtually every device and browser. Combining clips from different sources reliably requires a single, well-supported output container.
Each file is capped at 200 MB to keep processing reliable in the browser. Larger merges may run out of memory depending on your device.
Yes. The tool is fully responsive. Note that FFmpeg.wasm uses meaningful CPU and memory — desktop browsers handle large merges more comfortably.

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Ready to merge your videos?

Drop your files above and get a single MP4 in seconds — no account, no upload.

Merge Videos Now

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.