# Merge Videos Online - Join Multiple Clips into One File

> Free online video joiner: combine several MP4, MOV or MKV clips into one file, even when their resolution and frame rate differ. Processed locally.

- URL: https://qilingtools.com/en/video/merge
- Category: Video Tools (https://qilingtools.com/en/video)
- Tags: [Video](https://qilingtools.com/en/tags/video), [Merge & Split](https://qilingtools.com/en/tags/split-merge)
- Last updated: 2026-10-26
- Price: Free, no sign-up
- Privacy: Runs locally in the browser; files are never uploaded

Join several clips into one MP4, in the order you arrange them. The clips can have completely different resolutions, frame rates and formats — the sizes are unified automatically. Clips without an audio track get silence added, so the second half never ends up mute.

## How to use

1. Upload two or more videos and reorder them with ↑↓
2. Choose how to handle different frame sizes, plus output resolution and quality
3. Click start and download the merged video

## Features

- Mixes different resolutions, frame rates and formats
- Letterbox or crop-to-fill
- Silence added for clips without audio
- Single MP4 output
- FFmpeg runs locally

## FAQ

### What if the clips have different sizes?

Letterbox keeps every frame whole and fills the rest with black bars. Crop to fill zooms in and trims the edges so the picture fills the frame with no bars.

### Why is it slower than a desktop editor?

FFmpeg runs single-threaded in the browser and merging re-encodes every clip. A few short clips usually take a minute or two; long videos take longer.

### Are my files uploaded to a server?

No. Everything runs locally in your browser via WebAssembly. Files never leave your computer and are discarded when you close the page.

### Do I need to sign up or pay?

No. The site is completely free, requires no account, has no usage limits and adds no watermarks.

## Related tools

- [Compress Video](https://qilingtools.com/en/video/compress): Free online video compressor: shrink MP4, MOV and other formats with H.264 encoding and resolution scaling, at the strength you pick. Processed locally.
- [Convert Video](https://qilingtools.com/en/video/convert): Free online video converter: convert MOV, MKV, AVI, FLV, WebM and more to MP4 or WebM. Powered by FFmpeg, processed locally, no upload.
- [Trim Video](https://qilingtools.com/en/video/trim): Free online video trimmer: set start and end times to cut a clip; fast mode finishes in seconds without re-encoding. Processed locally, no upload.
- [Video to GIF](https://qilingtools.com/en/video/to-gif): Free online video to GIF converter: cut a clip and create a high-quality animated GIF with adjustable frame rate and width. Processed locally, no upload.
- [Extract Audio](https://qilingtools.com/en/video/extract-audio): Free online tool to extract audio from MP4, MOV and other videos as MP3, M4A or WAV. Processed locally, no upload.
- [Video Screenshot](https://qilingtools.com/en/video/screenshot): Free online video frame grabber: enter a timestamp and save that frame as a full-resolution PNG or JPG. Processed locally, no upload.
- [Mute Video](https://qilingtools.com/en/video/mute): Free online video muter: remove the audio track from a video in one click without re-encoding the picture. Finishes in seconds, processed locally, no upload.
- [Change Video Speed](https://qilingtools.com/en/video/speed): Free online video speed changer: slow a clip to 0.25x or speed it up to 4x. The audio follows along with its pitch preserved. Processed locally, no upload.