PureTools
Video Merger - Combine clips privately in your browser
Join multiple MP4 or WebM videos into one file without uploading them. Choose your output format, reorder clips, watch progress, and download a private result from your browser.
Private in-browser merge
Add clips, arrange the order, then merge
Your source videos stay on this device. The local processing engine loads only when you start a merge, then your temporary files are cleared when the tab closes.
Drop videos here
or · MP4 and WebM · MP4 max 500 MB total, WebM max 200 MB
Drag clips to reorder them, or use remove to fix the list before merging.
Preparing local video engine...
How to use the Video Merger
This tool combines separate MP4 or WebM clips into one downloadable video while keeping the files on your device. Use it for short camera clips, screen recordings, social drafts, lesson segments or any sequence that needs to become one clean file. If you need to reduce the final file size afterward, the Video Compressor can process the merged result without uploading it. To change the format of a clip before merging, use the Video Converter to convert it to a compatible format first.
- Add your videos - drop MP4 or WebM files onto the upload zone, or use the browse button. Add at least two clips. MP4 output accepts up to 500 MB total; WebM output accepts up to 200 MB on desktop and 100 MB on mobile.
- Check the clip order - the list shows the sequence that will appear in the final video. Put the opening clip first, follow with the middle clips, and place the ending clip last.
- Choose MP4 or WebM output - MP4 is the default because it plays on the widest range of phones, laptops and apps. WebM is useful when your workflow stays inside modern browsers and the clips are short enough for local encoding.
- Name the merged file - the filename box is pre-filled with a simple name. Change it before merging if you want the downloaded file to match a project, date or client label.
- Start the merge - click Merge videos. The first run may download a local processing engine of about 30 MB, then progress updates show preparation, conversion and final packaging.
- Download and clear - save the finished video from the result card. Your selected clips, temporary output and session settings are removed when you clear the page or close the tab.
Why local merging matters
Many online video joiners work by uploading every clip to a remote server before processing starts. That can be uncomfortable for personal videos, client drafts, classroom recordings or internal company footage. PureTools takes the opposite approach: the page loads a local video engine in your browser, processes the files there, and gives you the output directly. The trade-off is that very large projects depend on your device memory, but the privacy advantage is direct and easy to verify: the tool still works after the page has loaded, even if the network connection is unavailable.
Frequently asked questions
Are my videos uploaded anywhere?
No. The clips you select stay inside your browser tab and are processed on your own device. The page may load the video processing engine the first time you use it, but your actual footage is not sent to PureTools or to a third-party server. This matters for private family videos, client previews, school recordings and workplace material. Temporary data is held only for the current session and is erased when you clear the tool or close the tab. Your data is never used to train AI models or improve machine learning systems.
What video formats can I merge?
Version one is intentionally focused on MP4 and WebM input because they are the most practical browser-friendly formats for local video work. The output selector also offers MP4 and WebM. Keeping the format list small makes the result more predictable and reduces the chance of creating a file that plays in one app but fails in another. If your source video is MOV, AVI or MKV, convert or export it to MP4 first, then merge the clips here.
Why does the first merge take longer?
The first merge may need to download a local video engine of about 30 MB before processing can begin. That download happens once, then your browser can reuse the cached engine on later visits. The tool shows progress so you can tell whether it is preparing the engine, reading clips, converting or packaging the final file. After the first successful load, the page and engine can continue working offline as long as your browser keeps the cache.
Can I reorder clips before merging?
Yes. The clip list is designed around order control because the most common mistake in video merging is downloading a final file with the middle and ending clips reversed. Add all clips first, check the list from top to bottom, then reorder or remove anything that does not belong. The merge uses the visible list order, so the first item becomes the start of the output and the final item becomes the ending.
Which output format should I choose?
Choose MP4 when you want the merged video to play almost everywhere: phones, laptops, messaging apps, presentation tools and most editing software. Choose WebM when the video is mainly for modern browsers or web projects. MP4 is the default because it avoids the most common compatibility surprises. WebM can be useful for browser-based workflows, but some older mobile apps and desktop tools may not open it as smoothly.
Is there a file size limit?
Yes. MP4 output accepts up to 500 MB total input. WebM output is limited to 200 MB total on desktop browsers and 100 MB total on mobile browsers because WebM merging often requires full VP8/Opus re-encoding inside the tab. Browser-based video processing uses your device memory, so long high-resolution clips can fail on low-memory devices. For larger projects, choose MP4 output first, then compress or convert shorter clips afterward.
Does this work offline?
Yes, after the page and processing engine have loaded at least once. The first visit needs a network connection so the browser can cache the page, style files, script files and local video engine. After that, the merge itself runs on your device rather than on a server. If you close the tab, your selected clips and temporary output are cleared, but the tool files can remain cached so a later offline visit can still open.