Does resizing upload my image?

No. The image is scaled with a canvas in your browser. It is never sent to any server, so it stays completely private.

Will resizing reduce quality?

Making an image smaller is generally crisp because the browser uses high-quality smoothing. Enlarging beyond the original dimensions cannot add detail and will look softer, which is true of any resizer.

What formats can I export?

PNG (lossless), JPG and WebP (with an adjustable quality slider). JPG output is flattened onto a white background because it has no transparency.

How do I keep the proportions correct?

Leave "Keep aspect ratio" ticked. When you change the width the height updates automatically (and vice versa) so the image never looks stretched. Untick it to force exact width and height.

Can I enlarge a small image?

You can set dimensions larger than the original, but upscaling cannot invent detail — the result will look softer. For sharp results, resize down from a larger source rather than up from a small one.

What''s the difference between resize and crop?

Resizing scales the whole image to new dimensions (changing every pixel's size). Cropping cuts away part of the image to change its bounds. Use the image crop tool if you want to trim rather than scale.

Why is my resized JPG on a white background?

JPG has no transparency channel, so when you export to JPG the canvas is filled white first. Choose PNG or WebP if you need to preserve transparency.

Image Resize Tool — Gera Tools

Resize images to exact pixel dimensions

Set an image to an exact pixel width and height — handy for upload limits, thumbnails, avatars, banners and platform-specific size requirements. Lock the aspect ratio to scale proportionally, or unlock it to stretch to precise dimensions. It runs entirely in your browser.

How it works

When you load an image its native dimensions are read and pre-filled. With Keep aspect ratio on, editing one dimension recomputes the other from the original ratio, so nothing distorts. On Resize, the tool creates a <canvas> at your target size, sets imageSmoothingQuality = "high", and draws the source scaled to fit with ctx.drawImage(img, 0, 0, width, height). It exports with canvas.toDataURL — PNG is lossless, while JPG and WebP use your quality slider (JPG is filled white first since it has no alpha).

Example

A 4032×3024 phone photo that a form requires at 800px wide: load it, type 800 into Width with aspect ratio locked — Height auto-fills to 600 — pick JPG at 90%, and download photo-800x600.jpg. The downscale is sharp thanks to high-quality smoothing.

Target	Typical size
Avatar / profile	256×256 or 512×512
Web thumbnail	400×300
Full-width banner	1920×600

The resize is done with a <canvas> entirely on your device, so it is fast and your images are never uploaded.