Video Resizer

Resize video files via FFmpeg library in your browser!



A handy tool to resize video files. It accepts a wide range of video formats and works based on the famous FFmpeg library in JavaScript.


This web application is designed to resize video files. Simply drop a video file in the designated area within the app (top section). Then, adjust your settings (section I) and finally click on the - RESIZE - button. The input video can be from several formats such as .mp4, .webm, etc. To see the complete list of supported formats, please visit this Wikipedia page (https://en.wikipedia.org/wiki/FFmpeg). Within the settings section, there are five options to choose from. The first option is few common social media dimension (i.e. 640x360 px). The second option is choosing bitrate for the final audio and/or video. You can add both or just one of these values. The third option is to choose the final width or height in percent. For example, if you want the final video to have a 50% width comparing the original video, please enter 50 as the width value in the designated area and leave the height field empty. The app automatically adjusts the height value based on the width property. The fourth option is similar to the third option but you need to enter the desired final values for width and height in pixels. Please note that only one of the width or height values needs to be added not both of them. In option 5, both final width and height values are needed. The app adjusts the final video by adding padding to the final video when needed. So for option 5, please add both desired width and height value in pixels.

Technical Notes

This web application uses the FFmpeg library (https://github.com/ffmpegwasm/ffmpeg.wasm) which is compiled to JavaScript via the Emscripten compiler (https://github.com/emscripten-core/emscripten). Comparing speed to the original FFmpeg library running in C language, it has an acceptable performance if the input video file is not too large. Because the web app uses the memory and CPU from the browser, resizing large video files might introduce lag or slowness to the browser. So please keep this note in your mind when working with this app.

Video Resizer app is also available as a browser extension. As an extension, this app does not need an internet connection and can be used offline in your browser. Download links for three popular browsers are as follows: Chrome, Edge

If you found a bug in this page, or have a feature/function which you would like to see in this web app, please let us know by sending an email or through the discussion form below. Moreover, don't forget to check other web apps in webbrowsertools.com, we have many useful apps related to browser's privacy and security.

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