Use the free Video Joiner Online below: merge two or more MP4 or WebM clips into one single video, right in your browser. Your files never leave your device.
What the Video Joiner does
The Video Joiner Online puts two or more video clips together into one single video. You pick the clips in the order you want them to play, and the tool records them one after another into a new file. The result plays the first clip from start to end, then the second clip, then the third, and so on, with a hard cut between each clip. There are no transitions or title screens. That plain approach keeps the tool fast, free, and honest.
Everything happens in your browser. Your clips are never uploaded to a server, and you never need an account. The tool works with MP4, WebM, and MOV files, as long as your browser can play them. If a clip will not play in your browser, the joiner cannot use it either, because the joiner records what the browser plays.
How to use the Video Joiner
First, check the format line at the top of the tool. It tells you the exact output format your browser will produce, before you start. In Chrome and Edge that is usually MP4. In Firefox it is WebM. All of your clips are saved in that one format, no matter what format each clip started in.
Next, choose two or more video files. The tool lists every clip you add, with its length and file size, and it shows the total length of all clips together. The order in the list is the order in the final video, so pick the clips in the order you want them to play. Then press Join videos. The tool plays each clip in turn and records the result, so joining takes about as long as all of your clips put together. When it finishes, watch the joined video in the preview player and download it.
Worked example: two clips become one video
Here is a real test we ran with this tool. We joined two short clips. The first clip was 2.0 seconds long and 36.1 KB in size. The second clip was 3.0 seconds long and 50.9 KB in size. Together they added up to 5.0 seconds and 87.0 KB.
The tool joined them into one video that was 5.1 seconds long and 510,919 bytes in size, saved as MP4. The tiny extra tenth of a second comes from the recording process itself. The audio from both clips was kept, and the video stayed at 640 by 360 pixels, the size of both source clips. This is exactly what you should expect: total time equals the sum of your clips, and the output is a new, re-encoded file rather than a copy of the originals.
What stays the same, and what changes
The order of your clips stays exactly as you picked them, and the sound from each clip is kept. The frame size follows your source clips, because the tool records the picture it plays. What changes is the file itself: the joined video is re-encoded from scratch. That means the file size can grow or shrink compared with the clips you put in, and the picture quality can drop slightly, especially if a clip was already heavily compressed.
One more thing changes: the format. Mixed inputs still give you one video, in the single output format your browser supports.
Honest limitations
The joiner makes hard cuts only. It cannot fade between clips, cross-dissolve, or add music over the join. It cannot reorder clips after you add them, so if the order is wrong, clear the list and pick the clips again in the right order. Very long videos take a long time, because the tool records in real time: ten minutes of clips take about ten minutes to join, and the browser tab must stay open and in focus while it works.
Clips with different frame sizes still join, but the recording frame follows the clip that is playing. For the cleanest result, join clips with the same frame size. Also remember that the output is re-encoded, never lossless. If you need a perfect, bit-for-bit copy of your originals, this browser tool is not the right choice.
Good uses for the Video Joiner
This tool fits simple jobs. Put together phone clips from one afternoon into a single video to share. Join the parts of a short tutorial that you recorded in separate takes. Combine a title-free intro clip with the main clip, or stitch short scenes for a school project. For everyday jobs where one plain video is enough, it is quick and free.
Frequently asked questions
Can I join MP4 and WebM clips together? Yes. The tool plays each clip in your browser and records them all into the one output format your browser supports, so mixed input formats are fine.
How long does joining take? About the total length of your clips. Two clips of 2 and 3 seconds take about 5 seconds to join, plus a few seconds of setup. A 10-minute set of clips takes about 10 minutes.
Will the joined video lose quality? A little, yes. The output is re-encoded, not copied without change. The drop is small for most phone clips, but it is real, and the tool says so up front.
Do my videos leave my device? No. The whole job runs in your browser. Nothing is uploaded, and no account is needed.
Spanish version: Unir Videos Online