Image Resizer – Resize Images Online Free

Resize any photo or image to exact pixel dimensions, by percentage, or with one-tap social media presets — then download it as JPG, PNG or WebP. Private by design: your image never leaves your browser, because the resizing happens on your own device.

Resize Your Image

Drop an image here or click to browse — JPG, PNG, WebP, GIF or BMP from your device

No image loaded yet. Your image is processed locally — it is never uploaded.

Preset sizes

Instagram post · 1080×1080 Instagram portrait · 1080×1350 Facebook / link share · 1200×630 YouTube thumbnail · 1280×720 Full HD · 1920×1080 X / Twitter · 1600×900

Resize by percentage of the original

25% 50% 75% 100%

Width (px)

Height (px)

Lock aspect ratio (keep the picture's shape)

With the lock on, typing a width fills in the matching height automatically — the picture is never stretched.

Output format Same as original JPG PNG WebP

JPG / WebP quality — 90%

Resize Image

Your resized image

–

Original size	–
Output format	–
Output file size	–

Download Resized Image

How to Use the Image Resizer

Drop your image onto the box above, or click it to browse your device. The tool reads the picture locally and reports its original dimensions and file size — nothing is uploaded at any point. From there you have three ways to pick the new size: tap a preset for the platform you are posting to, tap a percentage to scale the picture down proportionally, or type exact pixel dimensions into the width and height boxes.

Leave Lock aspect ratio ticked unless you deliberately want to stretch the picture: with the lock on, changing the width recalculates the height so faces, logos and products keep their natural shape. Then choose the output format — keep the original, or convert to JPG for the smallest files, PNG for transparency and sharp graphics, or WebP for modern websites — set the quality if you picked JPG or WebP, and press Resize Image. Your resized picture is generated on the spot, with its real dimensions and file size shown, ready to download.

How Image Resizing Works

A digital image is a grid of pixels. Resizing redraws that grid at a different size: shrinking merges neighbouring pixels into averaged values, while enlarging has to invent new pixels by interpolating between the ones that exist — which is why upscaling can never add real detail. This tool does the redrawing with your browser's built-in canvas engine, the same technology photo editors use, running entirely on your device.

That one ratio — original height divided by original width — is the aspect ratio, and preserving it is what the lock does for you. Break it, and circles become ovals. The formula also runs the other way: give the height, and the matching width is height × (original width ÷ original height).

Worked Example

A typical phone photo is 4000 × 3000 pixels and about 4.6 MB as a JPG — far bigger than a blog or marketplace listing needs. Here is resizing it to a 1200-pixel-wide web image:

Ninety-one percent of the pixels were carrying no visible benefit at web display sizes — the 1200 × 900 version looks identical on a phone or laptop screen, loads in a fraction of the time, and sails under the upload limits that reject the original. That is why resizing, not re-photographing, is the right fix for "image too large" errors.

The Sizes Platforms Actually Want — What Most Resizers Don't Tell You

Every platform displays images at fixed sizes and quietly resizes anything bigger, usually worse than you would do it yourself. Feeding the exact display size keeps your picture sharp and your file small:

All five are one tap away in the presets above. One honest warning: presets crop nothing — they scale the whole picture to the target box, so a wide photo forced into a square preset will be squashed unless you unlock and accept the shape change. For a true crop, resize the long edge here first, then crop in your usual editor.

Limitations

Resizing cannot add detail: enlarging a small image makes it bigger, not sharper — for that, use the AI upscaler linked below. Extremely large images are limited by your device's memory and the browser's maximum canvas size, and animated GIFs are resized as a still first frame. Converting to JPG removes transparency, and repeated JPG saves at low quality gradually degrade an image, so keep your original file untouched as the master copy — this tool never modifies it.

Guides for This Tool

Frequently Asked Questions

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