[ toolsforcools ]
Welcome, Guest — free tools, no signup
Server Time: 2026-09-23
Home » Video Tools » Video Resizer

Video Resizer

Change video resolution or aspect ratio — 1080p, 720p, square 1:1 or vertical 9:16 for Reels, TikTok and Shorts.

🔒 Your video is processed locally in your browser. Your file is never uploaded.

Related tools

VideoVideo CompressorMake video files smaller for email, WhatsApp or upload limits — by quality level or target size, in your browser. VideoVideo TrimmerCut the start and end off a video, or keep just one part — instantly without re-encoding when possible. VideoVideo ConverterConvert videos between MP4, WebM, MOV and GIF in your browser — no upload, with quality and size options. Image · guideResize Images for InstagramCrop and resize photos to the exact Instagram sizes for posts, portrait posts, stories and reels.

You may also need

  • MP4 to WebM Converter — Convert MP4 videos to WebM (VP8/Opus) for websites and HTML5 video, right in your browser.
  • WebM to MP4 Converter — Convert WebM screen recordings and web videos to MP4 that plays on iPhone, Windows and editors.
  • MOV to MP4 Converter — Convert iPhone and QuickTime MOV videos to MP4 — usually in seconds, without losing quality.
  • Video to GIF Converter — Turn a part of a video into an animated GIF with good colors — choose start, length, size and frame rate.
  • Video to MP3 (Extract Audio) — Extract the sound from a video as MP3, M4A or WAV — in your browser, without uploading the video.

Popular next tools

Image CompressorQR Code Generator & ScannerImage Resizer & CropperAge CalculatorUnit & Currency Converter

All Video Tools »   Search all tools »

ADVERTISEMENT Google AdSense - Responsive Content Banner (600 x 100)

How to use the Video Resizer

  1. Choose a video.
  2. Pick a size preset and whether to crop or add bars.
  3. Click "Resize" and download the MP4.

Common use cases

  • Turn a landscape clip into a 9:16 vertical video for Reels, TikTok or Shorts
  • Make a square 1:1 video for a feed post
  • Downscale 4K footage to 1080p or 720p to save space

Example

A 1920×1080 landscape clip with "Vertical 9:16" and "Crop to fill" becomes a 1080×1920 MP4 cropped around the center.

What the Video Resizer does

It changes the frame size of a video. For social media that usually means changing the shape too: a normal landscape phone clip is 16:9, while Reels, TikTok and YouTube Shorts want vertical 9:16 (1080×1920) and feed posts look best square or 4:5. Crop to fill keeps the center and trims the sides. Fit inside keeps the whole picture and adds black bars. Keep the original shape only makes the video smaller, for example 4K down to 1080p.

The result is an H.264 MP4 with AAC audio, which every platform accepts. To make the file smaller as well, continue with the Video Compressor.

Frequently Asked Questions (FAQ)

Q: Is my file uploaded to a server?
A: No. The tool runs FFmpeg compiled to WebAssembly inside your browser tab. Your file is read directly from your device and the result is created locally. Only the video engine itself (open-source ffmpeg.wasm, about 10 MB compressed) is downloaded the first time, from a public CDN; after that it is cached.
Q: How big can the file be?
A: Up to about 500 MB works well on a computer and about 150 MB on a phone. Larger files may still work but can be slow or run out of browser memory. Trimming the clip or lowering the resolution first helps.
Q: Why is it slower than a desktop app?
A: The browser version of FFmpeg runs on a single CPU core and without hardware acceleration. A 1-minute 1080p re-encode typically takes 1–3 minutes. When possible the tools copy the streams without re-encoding, which takes only seconds.