Merge MP4 Files joins several MP4 videos into a single MP4, in the order you choose. It is made for everyday cases: phone clips from a trip, parts of a long recording that a camera split up, or screen recordings you want as one file. The sound is kept, and the files are joined in your browser without uploading them.
How to merge MP4 files
- Click Add videos and select all your MP4 files at once. You can add more with the same button.
- Check the order and move clips with ↑ and ↓.
- Choose the Frame size. Pick the size of your clips when they all come from the same device.
- Leave Keep the sound ticked.
- Click Merge videos and download the single MP4.
Common MP4 merges
| Situation | Tip |
|---|---|
| Phone clips from a day out | Pick the size of most clips; choose Fit inside if some are portrait |
| Action camera or dashcam split recording | Add the parts in file-name order; keep the camera’s size and frame rate |
| Screen recordings | Choose the recording’s own size so text stays sharp |
| Clips for Reels or TikTok | Choose 1080 × 1920 vertical and Fill the frame |
| Lesson or webinar in parts | 1280 × 720 at 30 fps keeps the file smaller |
Why the MP4 is re-encoded
Different MP4 files often use different sizes, frame rates and encoding settings, even from the same phone. To play as one smooth video, they are decoded and encoded again into one common MP4 with H.264 video and AAC sound. That takes longer than just sticking files together, but the result plays on almost any phone, computer or video site. Browsers that cannot encode MP4 save WebM instead.
Order and naming
Clips are listed in the order you add them. Cameras and phones name files in recording order, such as GH010123.MP4, GH020123.MP4, so sorting by name in the file picker usually gives the right sequence. Check the thumbnails in the list before merging.
iPhone MP4 and MOV files
iPhones save MOV files, often in HEVC. MOV works here too, but some browsers cannot read HEVC. If a clip will not load, try a recent Chrome or Edge, or Safari on a Mac.
After merging
A merged video can be large. Shrink it with the Video Compressor, or cut the start and end with the Video Cutter. For WebM, MOV or MKV clips, the main Merge Videos page explains all options.