Resize Video Dimensions Online for Free
Change video aspect ratios and downscale video resolution to fit Instagram, TikTok, YouTube, and email attachments.
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Your Privacy is Protected
- Your files are processed entirely in your browser
- No file upload — your video never leaves your device
- No account or registration required
- Files are not stored on any server
Resize Video Dimensions Online for Free
Scaling video dimensions is essential for reducing playback lag and fitting specific social media feed requirements.
Our browser engine uses Lanczos scaling algorithms in WebAssembly to preserve sharp details.
How to Use This Tool
- 1
Select your MP4 file
Drop your file onto the upload box or click to browse. The file stays on your device — it is never uploaded to any server.
- 2
Choose conversion options
Customize output settings or quality bitrate if needed. All parameters are pre-configured for optimal results.
- 3
Process in your browser
Click Convert to run the conversion locally using high-performance client-side WebAssembly and modern web APIs.
- 4
Download MP4
Click Download to instantly save your converted MP4 file directly to your local storage.
Why MediaConvertKit is Faster & More Private
| Feature | MediaConvertKit | CloudConvert / Zamzar |
|---|---|---|
| File Processing | 100% In-Browser (Local) | Uploaded to Remote Server |
| Privacy & Confidentiality | Guaranteed Zero Exposure | Files Stored Temporarily |
| Upload & Download Wait | Zero (Direct RAM Access) | Minutes (Bandwidth Dependent) |
| Price & Daily Limits | 100% Free & Unlimited | Paid Credits / Queues |
Supported Formats
Input Formats
Output Format
Frequently Asked Questions
- Yes, downscaling 4K or 1080p video to 720p drastically reduces file size.
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