How to merge videos
- Drop in two or more videos, or choose them all at once. You can add up to 20.
- Put them in order with the arrows. Remove any you don’t need.
- Choose a shape: keep the first clip’s, or pick landscape, vertical or square. Decide whether clips with a different shape get black bars or are cropped to fill the frame.
- Optionally, tick Fade through black between clips. Press Merge, check the preview and save.
Mix clips from different phones and cameras
Most free joiners only work when every clip has the same size, frame rate and format, and fail or play garbled video when they don’t. FitVideo redraws every clip into one frame and encodes the result fresh, so you can combine an iPhone video (HEVC, often sideways in the file), an Android clip, a WebM screen recording and an MKV game clip in one go. Videos recorded on their side are turned upright, and clips filmed at 120 or 240 fps for slow motion are brought down to 60 fps.
The sound of every clip is converted to the same format, 48 kHz stereo AAC, so it stays in sync from the first clip to the last. Clips without sound simply play silently for their length.
Landscape and vertical clips together
If you merge a landscape clip with a vertical one, one of them won’t match the frame. You choose what happens:
- Show all of it keeps the whole picture and adds black bars, at the sides or at the top and bottom.
- Fill the frame crops the edges so the clip covers the frame with no bars. It works best when the subject is in the middle.
For Reels, TikTok and Shorts, choose Vertical 9:16. For YouTube or a TV, choose Landscape 16:9. To make a single clip fit an app, with a blurred background instead of bars, use resize for social media.
How big will the merged video be?
The tool shows an estimate before you start. As a guide, a minute of 1080p video comes out at about 48 MB and a minute of 720p at about 22 MB. Merging doesn’t make your clips smaller: the result is roughly the size of the clips together at that quality. To send it on Discord, WhatsApp or by email, compress it afterwards.
Tips
- Trim first. Cut the unwanted start and end off each clip with trim video before merging, so the joins are clean.
- Use the fade when clips come from different places or times. A half-second fade through black hides jumps in light and sound.
- Keep it under 1 GB on phones. The merged video is built in your device’s memory. On a computer with 8 GB or more, much longer merges work.
- Order by name. If your files are numbered (clip1, clip2…), select them all at once and they’re added in the order your device lists them. Check the order before merging.
Questions
How many videos can I merge?
Up to 20 clips at a time. To join more, merge them in batches and then merge the results.
Can I merge videos with different sizes or formats?
Yes. Every clip is redrawn into one frame and re-encoded, so MP4, MOV, WebM, MKV and M4V clips of any size can be joined.
Does merging reduce quality?
The video is re-encoded at a high bitrate (about 6 Mbps at 1080p), which looks the same as the originals for most clips. Very detailed 4K footage is scaled to 1080p.
Will the sound stay in sync?
Yes. Each clip’s sound is converted to the same format and placed exactly under its picture. Clips without sound are silent for their length.
Is there a watermark?
No. FitVideo never adds a watermark or logo.
Are my videos uploaded?
No. The videos are joined in your browser, on your device. Nothing is sent anywhere.
Which browsers does it work in?
Chrome and Edge on a computer work best. Chrome on Android and Safari on iPhone (iOS 16.4 or later) and Mac work too, for shorter merges.
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