Video Side-by-Side Combiner - Compare Videos Online

Combine two videos side by side or stacked vertically. Compare gameplay, reactions, tutorials. Audio mixing options. Browser-based processing, no uploads.

Upload Videos

Left/Top Video

Drop video 1 here

Right/Bottom Video

Drop video 2 here

Privacy

All processing happens in your browser using FFmpeg WebAssembly. Your videos never leave your device—completely private and secure.

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Frequently Asked Questions

Side-by-side video combining places two videos next to each other horizontally or stacks them vertically in a single output video. This is commonly used for comparison videos, reaction content, before/after demonstrations, or showing multiple camera angles simultaneously.

Use horizontal (side-by-side) for landscape videos, gaming comparisons, or dual camera views. Use vertical (stacked) for portrait videos, top/bottom comparisons, or when screen height is more important than width. Choose based on your source video orientations and intended platform.

You can choose to match the shorter video's length (cutting the longer one) or loop the shorter video until it matches the longer one's duration. The default behavior uses the shorter duration for cleaner results.

The tool scales both videos to match heights (horizontal layout) or widths (vertical layout) while maintaining aspect ratios. Videos are centered in their respective frames, and any gaps are filled with black bars.

Choose from: left video audio only, right video audio only, mixed audio from both videos, or no audio. Audio mixing combines both tracks at equal volume. For more control, process with one audio source and add mixing in a separate audio editor.

Yes. The tool handles different aspect ratios by scaling and centering each video. Portrait and landscape videos can be combined, though this may result in letterboxing or pillarboxing to maintain proper dimensions.

Since each video is scaled to fit half the output frame, individual videos appear smaller than the original. Quality depends on output resolution settings. Higher resolution outputs preserve more detail but create larger files. The encoding process uses high-quality H.264 settings.

Side-by-side gives equal screen space to both videos, whereas picture-in-picture overlays a small video on top of a larger one. Use side-by-side for comparisons or dual content where both videos are equally important.

Processing time depends on video length, resolution, and your device performance. A 1-minute video typically processes in 30-90 seconds. Longer videos or higher resolutions take proportionally more time. All processing uses WebAssembly FFmpeg in your browser.

Browser memory limits typically allow videos up to 500MB each. Very large files may cause performance issues depending on your device's RAM and processing power. For best results, use videos under 200MB each.