Zolkit

Video Cropper

Crop videos to social media ratios, remove black bars, and preview the exact output frame before exporting. No upload, no watermark.

Drop your video here

or click to browse

MP4, MOV, AVI, MKV, WebM, WMV, FLV and more · up to 2 GB

Crop Preview

Upload a video to preview the cropped frame

Aspect Ratio

Crop Position

Output Quality

Crop Video Online — Remove Black Bars and Fit Social Media Ratios

Zolkit's Video Cropper crops video files entirely in your browser. Upload MP4, MOV, AVI, MKV, or WebM footage, choose a ratio like 9:16 for TikTok, 16:9 for YouTube, 1:1 square, or 4:5 for Instagram, and preview the exact output frame before exporting. The tool crops the picture area of the video, not the duration, and your file never leaves your device.

Private Browser Processing

Your video is processed locally with FFmpeg WebAssembly. No upload, no cloud storage, and no server-side queue.

Social Ratio Presets

One-click crops for 9:16, 16:9, 1:1, 4:5, 5:4, 4:3, and 21:9 cover the most common social and presentation formats.

Live Crop Preview

Preview the final frame before processing so faces, text, and products stay inside the crop area.

Crop Anchor Control

Use a 3×3 position grid to keep the top, bottom, left, right, or center of the original frame.

MP4 Export

Exports a standard H.264 MP4 that works on TikTok, Instagram, YouTube Shorts, iPhone, Android, and desktop players.

Free, No Watermark

Crop and download your video without signing up, installing software, or adding a watermark.

How to Crop a Video Online

  1. 1

    Upload your video by dragging it onto the page or clicking to browse.

  2. 2

    Choose an aspect ratio and crop position, then check the live preview and output dimensions.

  3. 3

    Click Crop Video, wait for processing, then download the cropped MP4.

Frequently Asked Questions

Can I crop video online for free?

Yes. Zolkit crops your video in the browser and exports a new MP4 without uploading your file. There is no watermark, account requirement, or server-side processing queue.

Can I crop an MP4 file?

Yes. MP4 is the best supported input and output format. You can also upload MOV, AVI, MKV, WebM, WMV, and many other common containers, but the exported file is a broadly compatible MP4.

Is cropping a video the same as cutting video length?

No. Cropping changes the visible frame area, such as removing black bars or turning 16:9 into 9:16. Cutting video length trims time from the beginning or end, which is a different tool.

Can I crop and download a YouTube video?

Zolkit does not download videos from YouTube or other third-party platforms. Use this tool with video files you own or have permission to edit by uploading the local file from your device.

What aspect ratio should I use for TikTok, Reels, or Shorts?

Use 9:16 for TikTok, Instagram Reels, and YouTube Shorts. If the important subject is not centered, use the crop position grid to keep the top, bottom, left, or right area in frame.

Will cropping reduce video quality?

Cropping pixels requires re-encoding the video. High quality preserves more detail, Balanced is the best default, and Smaller creates a lighter file with more compression.