Image Resizer — resize photos to exact pixels online
Resize a photo to exact pixel width and height, or scale it by percentage, with or without locking the aspect ratio. Free, and nothing leaves your device.
About the Resize image tool
Resizing changes how many pixels an image actually contains, which is a different operation from the one a website performs when it displays a large photo in a small box. In that second case the full file still downloads and the browser shrinks it on screen — the visitor pays for every pixel and sees none of the benefit. Resizing properly, before upload, is what makes a page fast.
The setting that causes the most confusion is the aspect ratio lock. Leave it on and entering a width computes the matching height, so the picture keeps its proportions. Turn it off and you can force any two numbers you like, but the image will stretch — faces widen, circles turn into ovals. If you need exact dimensions that do not match the original shape, resize with the lock on to cover the target, then crop the excess rather than distorting it.
DPI is the other source of confusion, and the short answer is that it does not apply here. A digital image has pixels, not inches; the DPI number stored in a file only tells a printer how densely to lay those pixels down on paper. Changing it alters nothing about the image itself. If a print shop asks for 300 DPI at a given paper size, what they actually need is a pixel count — multiply the inches by 300 and resize to that, and the requirement is met regardless of what the metadata says.
Screens complicate the arithmetic slightly. Phones and modern laptops pack two or three physical pixels into each layout pixel, so an image that fills a 400-pixel-wide column will look soft on those displays unless it contains around 800 pixels of real detail. Doubling the target width is the usual rule of thumb. Going beyond that buys nothing visible and costs your visitors bandwidth, which is the trade-off worth keeping in mind.
How it works
Load your image
Drop in a JPG, PNG or WebP. The original pixel dimensions appear so you can see what you are working from.
Enter pixels or a percentage
Type an exact width and height, or scale by percentage. Keep the aspect ratio locked unless you deliberately want to stretch it.
Download the result
Save the resized copy. Your original file is never modified, so you can come back and try different dimensions.
Frequently asked questions
- What size should I resize to?
- For a full-width image on a website, 1600 to 2000 pixels wide is generous on almost any screen. For a blog body image, 1000 to 1200 is plenty. Profile pictures rarely display above 400. Email attachments are comfortable at 1500. When in doubt, find out how wide the space is that will show it and use roughly double that, which covers high-density displays.
- Can I enlarge a small image?
- You can enter larger numbers, but there is no extra detail to recover — the tool interpolates new pixels from existing ones, so the result looks soft or blocky. Modest enlargement, up to around 150 percent, is often acceptable. Beyond that you need the original at a higher resolution, or a dedicated AI upscaler, which is a different kind of tool entirely.
- Why did the file size barely change?
- Resizing reduces pixel count, which normally cuts file size sharply — but if the image is a PNG of a photograph, or the encoder is writing at maximum quality, the saving can disappoint. Run the result through the Compress image tool afterwards, or convert it to JPG or WebP, and the size will drop the way you expected.
- Does resizing reduce quality?
- Making an image smaller discards pixels, which is lossy by definition, but it is the good kind of loss: you are throwing away detail that was never going to be visible at the display size. What does hurt is resizing repeatedly, or resizing up and back down. Always work from the original file rather than from a previous output.
- Is my photo uploaded to resize it?
- No. The image is drawn to a canvas at the new dimensions and read back out, all inside your browser tab. Nothing is transmitted, nothing is stored, and there is no account or file-size cap tied to a server plan — the only limit is your own device memory on very large images.
- How do I change the DPI to 300?
- You almost certainly do not need to. DPI is a note attached to the file telling a printer how tightly to space the pixels; it changes nothing about the image. When a printer asks for 300 DPI they mean enough pixels for the physical size — a 4 by 6 inch print at 300 DPI is 1200 by 1800 pixels. Resize to those dimensions and you have satisfied the request.
- Can I resize several images to the same size at once?
- This tool works on one image at a time so that you can see each result before saving it, which matters when photos in a batch have different orientations — a width that suits a landscape shot will crop or letterbox a portrait one. If you have a large uniform batch and identical dimensions genuinely are correct for all of them, a desktop tool with scripting will be faster.