Helpful Guide

Image Information

Check Image Dimensions

Knowing an image's exact pixel dimensions matters more than it sounds. It determines whether a photo is sharp on a retina screen, whether it can be printed at a given size, and whether a platform will crop it.

Drop a file here to read its width, height, simplified aspect ratio and megapixel count instantly.

Drag images here

Add several images to compare them side by side

How to use this tool

  1. 1Add one or more images.
  2. 2Read the width and height reported for each file in pixels.
  3. 3Check the simplified aspect ratio next to the dimensions.
  4. 4Use the resize or crop tools if the numbers are not what you need.

Dimensions, resolution and print size

Pixel dimensions are absolute. Resolution in DPI only matters when printing, because it describes how many of those pixels are packed into each inch of paper. A 3000×2000 photo is 10×6.7 inches at 300 DPI and 25×16.7 inches at 120 DPI, with no change to the file at all.

Common target sizes

Full-width hero images on desktop layouts are typically 1920 px wide. Blog body images rarely need more than 1200 px. Thumbnails sit between 300 and 600 px. Serving anything substantially larger than its display size wastes bandwidth and slows the page for no visible benefit.

Megapixels explained

Megapixels are simply width multiplied by height, divided by a million. A 4000×3000 photo is 12 MP. The figure predicts how much detail is available for cropping and printing, not how good the image looks; lens quality and lighting matter far more.

Frequently Asked Questions

Where does this read dimensions from?

The image is decoded in your browser and the intrinsic pixel size is read directly, so the result is accurate even if metadata is wrong.

Does it work for WebP and AVIF?

Yes, provided your browser can decode the format. Current browsers handle WebP everywhere and AVIF in most cases.

What is a simplified aspect ratio?

Width and height divided by their greatest common divisor. 1920×1080 simplifies to 16:9.

Are my files uploaded?

No. Everything happens locally in the browser tab.