ImgResize resizes, crops and converts images — to exact pixel dimensions, a percentage, a longest side, platform presets, or a rectangle you drag yourself — and it does all of that inside your browser, in one file or a batch.

The tool that isn’t an upload form

The typical online resizer is an upload button backed by a queue: your picture travels to a machine you can’t see, waits its turn and comes back. That costs you two things — privacy, since the file may be a passport photo or a client’s product shots passing through unknown infrastructure, and time, since the pipeline is sized for the operator’s quotas rather than your deadline.

This site removes the round trip entirely. Decoding, resampling, cropping and re-encoding are performed by JavaScript on the device in front of you, which any modern browser handles easily. With no destination to upload to, there is no upload — disconnect the Wi-Fi after loading and nothing changes.

On the site

• The resizer itself — exact pixels, percentage or longest edge; ratio cropping with a draggable frame; JPEG, PNG and WebP conversion; single images or batches.
• Platform size guide — the dimensions each social network really displays, with one-click crop-to-fill presets.
• Resampling explained — nearest-neighbor, bilinear, bicubic and Lanczos compared, i.e. why one resize stays crisp and another turns mushy.
• When not to upscale — the situations where enlarging is the wrong move, and the alternatives that work.

Under the hood

Everything here is static files on Cloudflare’s edge; there is no image backend to go down or to leak. The resizer is a few hundred lines of dependency-free JavaScript built on createImageBitmap — so EXIF orientation is honored — and the canvas high-quality resampler.

A dropped picture is resized, cropped and re-encoded inside your own tab. AI coding and writing assistants produced the resizer’s code and the guides to the maintainers’ brief. Automated tests confirm that an 800×600 test image comes out exactly 400×300 by width, 1080×1080 or 1280×720 by preset, and 600×600 by a 1:1 crop.

A small team looks after ImgResize independently, alongside sibling tools such as the QR code generator. Something broken, or a platform dimension we got wrong? Contact us — corrections get priority.