Image Resizer
Resize to exact dimensions, by percentage, or with a platform preset.
Your files never leave your device — processing happens in your browser.
Drop an image here
or paste from your clipboard. Your file is processed on this device and is never uploaded.
Three ways to resize, and when each is right
By dimensions when something has given you an exact number to hit — a print size, a CMS field, a form that specifies maximum pixels.
By percentage when the image is simply too big and you do not much care about the exact result. 50% is the usual starting point and is often enough on its own.
By preset when you are posting somewhere specific and would otherwise be looking up the current recommended size.
Resize first, then compress
If you are trying to get a photo under a size limit, resizing is far more effective than compressing and it costs much less quality. Halving each side quarters the number of pixels; the file usually ends up well under a quarter of its original size, and — critically — it still looks sharp, because you removed pixels rather than discarding detail from the ones you kept.
Compressing hard, by contrast, keeps every pixel but degrades all of them. A 4000-pixel photo squeezed to 200 KB looks noticeably worse than the same photo resized to 1200 pixels and then compressed gently to the same 200 KB.
How big does an image actually need to be?
- On a website — 1200 to 1920 pixels wide is plenty for a full-width image. Anything larger is downloaded and then thrown away by the browser.
- Emailed or messaged — 1200 pixels is generous. Most messaging apps re-compress anyway.
- Printed — this is the one case for keeping the full resolution. Roughly 300 pixels per printed inch, so a 6×4 inch print wants about 1800×1200.
- Archived — do not resize at all. Keep the original and resize copies.
Quality of the resampling
Shrinking an image means deciding what each new pixel should be, given several old ones. Done carelessly — by sampling one source pixel per output pixel — fine detail turns into shimmering, jagged-looking noise. This tool halves the image repeatedly until it is close to the target and only then does the final exact step, so every source pixel contributes to the result.
Questions
Is my image uploaded?
No. Resizing happens in your browser on your own device. Open developer tools, watch the Network tab while you resize, and you will see no request carrying your image — the tool also keeps working with the network disconnected.
Why won’t it make my image bigger?
Enlarging is off by default because it cannot add detail that was never captured. Scaling a 500-pixel image to 2000 pixels produces a soft, four-times-larger file containing exactly the same information. You can switch enlarging on if you genuinely need the pixel dimensions, but the result will look softer than the original.
What does "keep the aspect ratio" do?
It stops the image being stretched. With it on, entering only a width works out the height for you; entering both fits the image inside that box rather than distorting it to fill exactly. Turn it off only when you deliberately want a stretched image.
Why does the result not exactly match the preset dimensions?
Presets keep your image’s proportions, so unless your image already has the preset’s aspect ratio it will fit inside those dimensions rather than filling them exactly. Filling exactly would mean cropping parts of your image away, which this tool will not do without being asked.
Does resizing reduce file size?
Substantially — usually more than you would expect. Halving both sides quarters the pixel count, and file size typically drops by rather more than three quarters. Resizing before compressing is the most effective way to get a large photo under a strict size limit.
Will resizing make my image blurry?
Not when shrinking. This tool halves the image repeatedly before the final step rather than jumping straight to the target size, which avoids the aliasing and jagged edges that make a naive resize look cheap. Enlarging always softens an image, which is why it is off by default.