Image Resizer - Resize Photos to Exact Pixels Online
Resize JPG, PNG, and WebP images to exact pixel dimensions or by percentage, with aspect ratio locking — processed locally, never uploaded.
Load an image, enter a target width and height in pixels or a scale percentage, pick an output format and quality, and download the resized copy. All resizing happens in your browser with the canvas API.
Image Resizer - Resize Photos to Exact Pixels Online
Resize JPG, PNG, and WebP images to exact pixel dimensions or by percentage, with aspect ratio locking — processed locally, never uploaded.
Your image is resized locally in your browser and never leaves your device.
90%
Dimension calculator
Planning a resize? Enter your image's original dimensions and the width you want, and get the matching height that keeps the aspect ratio — plus the megapixel count before and after.
About the image resizer
Every platform wants images at a different size: a profile picture here, a 1920-pixel hero banner there, a strict pixel limit on a government form somewhere else. This image resizer changes the pixel dimensions of JPG, PNG, and WebP images to whatever a site or print job demands, and it does the work entirely inside your browser — your photos are decoded, scaled on a canvas, re-encoded, and downloaded without ever touching a server.
You can resize in two ways. Pixel mode lets you type an exact width and height, which is what you need when a form says an image must be, say, 600 by 600 pixels. With the aspect-ratio lock enabled, editing one dimension automatically updates the other so the picture never looks stretched or squashed; disable the lock only when you deliberately want a non-proportional resize. Percentage mode scales the whole image by a factor — 50% halves both dimensions, which cuts the pixel count to a quarter — and is the fastest way to shrink a batch of photos that just need to be "smaller" rather than an exact size.
Before downloading, choose the output format and quality. JPG at quality 80–90 is the sensible default for photographs; PNG keeps perfect detail and transparency for graphics and screenshots; WebP usually produces the smallest files of the three. Because scaling is done with the browser's high-quality canvas interpolation, downsized images stay crisp. Enlarging is also possible, but upscaling cannot invent detail: a small image blown up to poster size will look soft, so it is always better to start from the largest original you have.
If you only need the numbers, the dimension calculator below the tool answers the everyday question "if I make it 1200 wide, how tall will it be?" without loading any file. Enter the original width and height and your intended new width, and it returns the proportional height rounded to the nearest pixel along with the megapixel count before and after — handy for estimating how much smaller a file will get, since file size tracks pixel count closely. Everything on this page runs locally, works offline once loaded, and is free with no watermarks, sign-ups, or file limits.
Image resize examples
Common resizing jobs and what to enter for them.
| Task | Settings | Note |
|---|---|---|
| Make a 6000 × 4000 photo fit a 1500 px wide blog column | Pixels mode, width 1500, aspect lock on → 1500 × 1000 | The lock fills in the proportional height automatically, so the photo is not distorted. |
| Halve a screenshot for documentation | Percentage mode, scale 50% | Half the width and half the height means the output has a quarter of the pixels — and a much smaller file. |
| Square 600 × 600 avatar from a portrait photo | Pixels mode, 600 × 600, aspect lock off | Forcing a square from a non-square photo stretches it slightly; crop to a square first if that matters. |
| Dimension calculator: 3840 × 2160 original, new width 1280 | Height 720, 8.29 MP down to 0.92 MP | 1280 × 2160 ÷ 3840 = 720. The pixel count drops by about 89%, and the file size falls with it. |
How to resize an image
- Choose a JPG, PNG, or WebP image with the file picker — it is processed locally and never uploaded.
- Pick a resize mode: enter an exact width and height in pixels (with the aspect-ratio lock keeping proportions), or a scale percentage.
- Select the output format and quality for the exported file.
- Click Resize & Download to save the resized image to your device.
Image resizer FAQ
Is my photo uploaded when I resize it?
No. The image is read with your browser's File API, scaled on an in-memory canvas, and re-encoded on your device. Nothing is transmitted anywhere, so the tool is safe for private photos and documents.
How do I resize an image without distorting it?
Keep the aspect-ratio lock enabled. When you type a new width, the matching height is calculated automatically (and vice versa), so the proportions of the original are preserved exactly.
Can I enlarge a small image?
Yes, you can enter dimensions larger than the original, but upscaling cannot create detail that was never captured. Modest enlargements look fine; extreme ones look soft or blurry. Always start from the highest-resolution original you have.
What is the difference between resizing and cropping?
Resizing scales the whole picture to new dimensions and keeps everything in the frame. Cropping cuts away part of the picture to change its composition or aspect ratio. To get a square from a rectangular photo without stretching, crop first, then resize.
Which output format should I choose?
Use JPG for photographs, PNG for screenshots, graphics, or anything needing transparency, and WebP when you want the smallest file and know the destination supports it. Quality 80–90 is a good balance of size and fidelity for lossy formats.
Does reducing dimensions reduce file size?
Dramatically. File size scales roughly with the number of pixels, so halving both dimensions cuts the pixel count — and typically the file size — to about a quarter. Resizing is usually more effective than lowering quality alone.