Resize an image
Make a photo small enough to email or upload, and see the new size before you save it. Nothing leaves your computer.
Enter the upload limit in KB (1 KB = 1,000 bytes). Quality and dimensions are adjusted automatically. PNG keeps its lossless encoding and may need a much smaller image.
No image yet.
The new size is shown before you save
Most resizers make you download the file to find out whether it is small enough, then go back and try again. This one encodes as you change the settings and tells you what the result weighs, or use Maximum file size to find settings below your upload limit automatically.
That is possible precisely because nothing is uploaded. The work happens on your own processor, so trying five settings costs five seconds rather than five round trips to somebody's server.
Two dials, and they do different things
Size changes how many pixels there are. A 4000 pixel wide photograph reduced to 1600 has about a sixth of the pixels, and that alone usually does most of the work.
Quality changes how many bytes each pixel costs. At 80% a JPG is visually indistinguishable from the original for almost anyone; below about 60% you start to see blocking around edges and lettering. Doing both together gets a far smaller file than pushing either one on its own.
What size do you actually need
Email or messaging: 1600 pixels on the longest edge at 80%. A four megabyte phone photo comes out around 250 KB and still looks right full screen.
A website or a blog post: 1200 to 1600 wide, and WebP if the site accepts it. Anything larger is bytes the visitor pays for and never sees.
An upload form with a hard limit: choose Maximum file size, enter the limit in KB, and let the tool adjust quality and dimensions. The saved file is checked against the limit in bytes.
Printing: resist. Print wants every pixel you have, so resize a copy and keep the original.
It will not enlarge past the original
Asking for 4000 pixels from a 1000 pixel image cannot recover detail that was never captured. All an upscale produces is a bigger, softer file, so this stops at the original resolution and tells you it did rather than pretending.
Pick the right format
JPG for photographs. WebP for photographs where whatever receives it is modern, since it is 25 to 35% smaller again at the same visible quality. PNG for screenshots, logos, diagrams and anything with transparency, and never for a photograph: it is lossless, so it will stay large no matter how far you shrink it.
To change format without changing size, the image converter does that alone.
Common questions
- Is my photo uploaded?
- No. It is read from your own disk, resized in your browser, and handed straight back. Nothing is sent to us or to anyone else, and nothing is stored. Watch the network tab in your browser developer tools while you use it and no request goes out.
- What size should I use for an email attachment?
- A longest edge of about 1600 pixels at 80% quality is the usual answer. That is still sharp on any screen, prints acceptably at postcard size, and takes a typical phone photo from four or five megabytes to around a quarter of a megabyte. If the limit is strict, drop the longest edge to 1200.
- Why is my file still large after resizing?
- Almost always because the output is PNG. PNG is lossless, so it stores every pixel exactly and a photograph stays big however small you make it. Photographs want JPG or WebP. PNG is for screenshots, logos and anything with flat colour or transparency.
- Does resizing lose quality?
- Making an image smaller discards pixels, which is exactly what you want and is invisible at the new size. Making it larger cannot invent detail that was never captured, so this will not enlarge past the original resolution: an upscale only produces a bigger, blurrier file.
- What is the difference between resizing and compressing?
- Resizing changes how many pixels there are. Compressing changes how many bytes each pixel costs. This page does both, because on a photograph they are the two halves of the same job, and doing only one usually leaves the file bigger than it needs to be.