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Image Resizer – Resize Photos in Pixels, Percent, CM or Inches

Change the dimensions of one photo or a whole batch — in pixels, by percentage, or in centimetres and inches at the DPI you choose. Fast, free and done on your own device.

Your files stay on your device

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How to use the image resizer

  1. Add your images (up to 20). The first photo’s size is shown to help you choose.
  2. Choose how to resize: Pixels, %, cm or inch.
  3. Enter the new width and/or height. With Keep aspect ratio on, the other side follows automatically.
  4. For cm or inches, set the DPI (300 for prints).
  5. Pick the output format and tap Resize. Save each image or download all as a ZIP.

Pixels, centimetres and DPI

A digital photo is a grid of pixels. A photo 4,000 pixels wide and 3,000 high has 12 million pixels (12 megapixels). Printed size depends on how many pixels you print per inch:

Pixels = size in inches × DPI   ·   Pixels = size in cm ÷ 2.54 × DPI

Examples

You needDPIPixels
3.5 × 4.5 cm passport photo300413 × 531
2 × 2 inch photo300600 × 600
A4 page (21 × 29.7 cm)3002480 × 3508
Full HD screen—1920 × 1080

Keeping the aspect ratio

The aspect ratio is width divided by height. A 4,000 × 3,000 photo has a 4:3 ratio. Resize the width to 1,200 with the ratio locked and the height becomes 900. Unlock it and type both sizes only if you really want to stretch or squash the image — otherwise use crop image to change the shape.

Tips

  • Resizing down is safe; resizing up loses sharpness. Start with the largest original you have.
  • Exam and job forms often need exact pixels and a KB limit. The photo & signature resizer does both together.
  • Need a smaller file, not smaller dimensions? Use the image compressor.
  • PNG for graphics, JPG for photos. PNG keeps text and logos crisp; JPG makes photos much smaller.

Why some resized photos look blurry

Shrinking a photo throws away pixels, and doing it in one big step can make edges look jagged. This tool reduces large photos in several halving steps with high-quality smoothing, so text and faces stay crisp even when a 4,000-pixel photo becomes 400 pixels wide.

Enlarging is different: the tool has to invent pixels between the existing ones, so the result is soft. If you need a bigger photo, start from the original camera file rather than a copy saved from WhatsApp or a website, which may already have been made smaller.

Who uses an image resizer

  • Students and applicants matching photo sizes for forms.
  • Online sellers preparing product photos in the size a marketplace asks for.
  • Designers and bloggers making images fit a layout.
  • Office staff shrinking scans before emailing.

Frequently asked questions

How do I resize an image without stretching it?

Keep “Keep aspect ratio” turned on and change only the width (or only the height). The other side is calculated automatically so the picture keeps its shape.

How do I resize a photo to centimetres, like 3.5 × 4.5 cm?

Choose “cm”, enter the width and height, and set the DPI (300 is standard for printing). The tool converts it to pixels — 3.5 × 4.5 cm at 300 DPI is 413 × 531 pixels — and writes the DPI into JPG files.

What is DPI and does it matter?

DPI (dots per inch) links pixels to printed size. A 600-pixel-wide photo printed at 300 DPI is 2 inches wide. For screens and most online forms only the pixel size matters; DPI matters when you print.

Can I make a small photo bigger?

Yes, but enlarging can’t add detail that isn’t there, so a small photo will look soft or blurry when made much bigger. Shrinking always looks clean.

Can I resize several photos at once?

Yes. Add up to 20 images and they all get the same setting. With “Keep aspect ratio” on, each photo keeps its own shape.

Are my photos uploaded?

No — resizing happens in your browser and your photos never leave your device.

What size should a photo be for email or WhatsApp?

Around 1,280 to 1,920 pixels on the longest side looks sharp on phones and laptops and keeps files small. Messaging apps resize large photos anyway, so sending a smaller photo saves data without visible loss.

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