Image Cropper

What is the Image Cropper?

The Image Cropper is a free, browser-based tool that lets you cut an image down to exactly the part you want to keep. Add a photo or screenshot, drag a crop box over the area that matters, optionally lock it to a fixed aspect ratio like 1:1 or 16:9, and download the trimmed result. Every step runs on your own device — the picture is drawn to a local canvas and is never uploaded, stored, or logged.

How to use it

1. Add an image — tap or click the drop zone to choose a file, or drag and drop one onto it.
2. A crop box appears over the preview. Drag the box to move it; drag any corner handle to resize it.
3. Pick an aspect ratio (Free, 1:1, 4:3, 16:9, 3:4, or 9:16) if you need a fixed shape; the box stays locked to that ratio while you adjust it.
4. Choose a save format, then tap Crop & download. Answer in, answer out, done.

The method behind it

Cropping is a coordinate operation, not a filter. When you place the crop box, the tool records its position and size in the preview, then scales those numbers back up to the image's natural pixel grid so nothing is lost on small screens. It uses the canvas drawImage(source, sx, sy, sw, sh, 0, 0, sw, sh) call to copy only the selected rectangle of source pixels into a fresh canvas the exact size of your selection. The kept pixels are untouched — there is no resampling of the region you keep — and the canvas is exported with toBlob() so the download is a real image file, not a screenshot.

Aspect-ratio presets work by constraining the box geometry: when a ratio is active, resizing one side automatically derives the other so width ÷ height always equals 1 for a square or 16 ÷ 9 for a widescreen frame.

Examples

• Square avatar from a portrait: load a 4000×3000 photo, choose 1:1, drag the box over the face, and download a perfectly square crop ready for a profile picture.
• 16:9 thumbnail: take a 1200×1200 screenshot, choose 16:9, and trim it to a clean widescreen frame for a video thumbnail or slide.
• Receipt close-up: drop a phone photo of a receipt, choose Free, tighten the box around just the total, and save a focused crop without the background.

Common use cases

Cropping social-media avatars and banners to the platform's required shape; trimming screenshots before pasting them into a doc or ticket; making square product shots for a store listing; cutting a 9:16 vertical frame for a phone wallpaper or Reel; removing dead space and bystanders from a photo; and preparing ID or document scans where you must not send the file to a third-party server.

Why use this one

Most online croppers upload your file before they let you touch it. This one does not: the image is loaded into a canvas in your browser and the crop happens locally, so private screenshots, ID scans, and client mockups never leave your device. The crop box is built touch-first — you can move and resize it with one finger on a phone — and the aspect-ratio presets snap to common shapes so you do not have to eyeball a square. There is no watermark, no sign-up, and the kept region exports at full source resolution.

It is part of a small image toolkit. To change pixel dimensions instead of trimming, use the Image Resizer; to shrink a file's weight, try the Image Compressor; to swap formats, reach for PNG to JPG; and to embed an image inline, use Image to Base64.

Frequently asked questions