ALTools

Social Media Resize

Resize videos for TikTok, YouTube Shorts, Instagram Reels, and more.

How to use this tool — step-by-step guide

How Social Media Resize Works

Choose a preset for TikTok, YouTube Shorts, Instagram Reels, or enter custom width, height, and frame rate. Upload your source video and ALTools loads it locally—no server upload and no account required.

The tool scales your full frame to fit the target aspect ratio and exports an MP4 on your device. When the source and target shapes differ, black bars are added by default; enable Blurred background to fill the empty areas with a soft copy of your footage.

Use it to turn horizontal clips into vertical Shorts or Reels, repurpose one edit for multiple platforms, or hit exact dimensions required by an ad network or client brief.

Resizing and export happen locally, so drafts stay on your device without cloud queues. Processing time grows with length and resolution, but your files are not transmitted elsewhere.

You get an MP4 sized for the platform you selected—ready to upload from your phone or desktop without opening a full editing suite.

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Frequently Asked Questions

What platforms are supported?

One-click presets cover TikTok, YouTube Shorts, Instagram Reels, and many more — or set a custom width, height, and frame rate.

Will my video be cropped?

The full frame is kept and scaled to fit. When aspect ratios differ, black bars are added by default. Turn on Blurred background to replace them with a blurred version of your video.

Is processing done locally?

Yes — resize and export to MP4 happen entirely on your device.