Image Resizer

The Image Resizer scales a picture to the exact width and height in pixels that you type and saves it as a high-quality JPG. Use it to meet the pixel dimensions a form or platform asks for, to shrink huge phone photos before emailing them, or to prepare images at the size a web page actually displays.

Using the width and height boxes

When an image loads, the Width (px) and Height (px) boxes fill with its current size and the preview shows its file size. Type the new dimensions and click Process image. The whole picture is scaled into the new rectangle; nothing is cut off.

The two boxes are independent: changing the width does not update the height automatically. If the new width and height don't share the original's proportions, the picture is stretched or squashed. To keep proportions, calculate the height yourself:

new height = new width × original height ÷ original width

Worked examples

• A 4032 × 3024 iPhone photo resized to 1600 wide: 1600 × 3024 ÷ 4032 = 1200, so enter 1600 × 1200.
• A 3000 × 2000 DSLR image for a 1200 px website slot: 1200 × 2000 ÷ 3000 = 800, giving 1200 × 800.
• A 1920 × 1080 screenshot for a 1280 px wide YouTube thumbnail: 1280 × 1080 ÷ 1920 = 720, which is exactly 1280 × 720.

The aspect ratio calculator does this sum for any size. When the target has a different shape, such as a square from a landscape photo, crop to that shape first with the image cropper and resize afterwards, otherwise people and objects end up distorted.

What the output file looks like

• Format: always JPG at 92% quality, whatever you upload (JPG, PNG, WEBP or HEIC).
• Transparency: JPG has none, and transparent areas come out black. Resize logos with transparent backgrounds another way, or accept a solid background.
• Metadata: EXIF details such as date taken and GPS location are not carried into the new file.
• Check before downloading: the Result label shows the final dimensions and size in KB.

Pixel dimensions versus file size

Many application portals state a limit in KB rather than in pixels. Smaller dimensions nearly always mean a smaller file, since halving both width and height leaves a quarter of the pixels. If the resized file is still above a KB limit, run it through the image compressor at a lower quality setting. When a form fixes both the pixel size and a KB range, as exam application forms often do, resize the image to an exact KB limit and set the dimensions in the same pass.

For printing, pixels relate to physical size through DPI: a 6 × 4 inch print at 300 DPI needs 1800 × 1200 pixels. Resizing below that makes prints soft.

Enlarging has limits

You can type dimensions larger than the original, but upscaling only spreads the existing pixels further apart. The browser smooths the result, so it looks softer rather than more detailed, and a blurry 300 px image will not become sharp at 1200 px. Start from the largest original you have. On very large reductions, fine repeating patterns such as fabric or brickwork can shimmer (moiré); resizing in two steps, halving first and then going to the final size, sometimes gives a cleaner result.

The resizing is done by your browser on your own device; nothing is uploaded.