Resize Image
Change image dimensions in pixels.
How to use Resize Image
Add the image or images you want to resize.
Enter the target width and/or height in pixels. Keep "Maintain aspect ratio" enabled to avoid distortion.
Click Resize.
Download the resized images.
Resolution, dimensions and file size are three different things
Dimensions are the pixel count — 1920 × 1080. File size is the bytes on disk, which depends on dimensions *and* compression. DPI is a printing instruction and has no effect whatsoever on how an image appears on screen, despite being the thing people are most often told to change.
This matters because the advice "make it 300 DPI" is meaningless for a web image. A 1200 × 800 image is 1200 × 800 pixels whether it is tagged 72 or 300 DPI; the tag only tells a printer how large to print it. For screens, only pixels exist.
Downsizing and upsizing are not symmetrical
Making an image smaller is safe. The algorithm averages groups of pixels into one, and the result is usually sharper-looking than the original because averaging suppresses noise. There is no quality penalty worth worrying about.
Making it larger is invention. The extra pixels do not exist and must be guessed from their neighbours, so the image gets bigger and softer — always. Beyond about 200% the softness is obvious to anyone. If you need a large image, go back to the source: the original camera file, or the vector if there is one.
Keeping the proportions
Changing width and height independently stretches the image, and human faces make stretching immediately obvious. Keep the aspect ratio locked and set one dimension; the other follows.
When you need exact dimensions that do not match the original ratio — a square profile picture from a landscape photo, say — crop rather than stretch. Cropping loses part of the image, which is honest. Stretching keeps everything and makes it wrong.
- Instagram square 1080 × 1080, portrait 1080 × 1350, story 1080 × 1920.
- Open Graph preview (link cards on Facebook, LinkedIn, X): 1200 × 630.
- YouTube thumbnail: 1280 × 720.
- Full-width web hero: 1920-2400 px wide, more only for a specific reason.
- In-article images: 800-1200 px wide is plenty on any screen.
Resize for the display size, then double it
Retina and high-density screens pack two or three physical pixels into each CSS pixel, so an image displayed 800 px wide is drawn on roughly 1600 physical pixels on most modern phones and laptops. Supplying exactly 800 px looks soft on the devices most people are reading on.
Export at twice the display width and compress a little harder to offset it — a 1600 px image at quality 80 is both sharper and smaller than an 800 px image at quality 95. It is the single easiest win in image delivery.
Every step runs inside your browser, using the WebAssembly and Canvas APIs your device already ships with. No file is uploaded, no copy is kept, and nothing sits in a queue on a server waiting to be deleted — which is also why the tool keeps working with the network disconnected.
Frequently Asked Questions
How do I resize without distorting the image?
Leave "Maintain aspect ratio" enabled and set only one dimension — the other is calculated automatically.
Can I make an image larger?
Yes, but enlarging cannot add detail that isn't in the original, so big upscales may look soft.
Which formats are supported?
JPG, PNG and WEBP, and the output keeps the original format.
How do I resize an image without losing quality?
Make it smaller, not larger. Downsizing preserves quality and often looks sharper. Enlarging always softens, because the added pixels have to be guessed. If you need larger, return to the original file.
Does resizing change the file size?
Substantially. File size scales with pixel count, so halving both dimensions removes about 75% of the data. Resizing is the most effective way to shrink an image — far more so than adjusting compression.
Should I change the DPI for the web?
No — DPI has no effect on screen. Browsers use pixel dimensions and ignore the DPI tag entirely. It only matters for print, where it tells the printer how large to lay the image down.
How do I resize to an exact size without stretching?
Crop, then resize. Crop to the target aspect ratio first, then scale to the exact pixel dimensions. Setting width and height independently distorts the image, which is obvious the moment a face is involved.
What size should images be on a website?
Roughly twice their displayed width, to look sharp on high-density screens. In practice: 1920-2400 px for full-width heroes, 800-1200 px for in-article images, 300-400 px for thumbnails.
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