Image tool / 20
Image Dimensions Checker
Read an image’s exact pixel dimensions, aspect ratio, megapixels, size, and MIME type.
Image Dimensions Checker: TOEA asks the browser decoder for the image’s natural width and height, then derives its ratio and megapixel count. Runs 100% locally in your browser with zero server file uploads.
- Category
- Image tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
JPG, PNG, WebP, or GIF · up to 30 MB
Reading the aspect ratio
The ratio is shown as a decimal against 1. Common values: 1.7778 is 16:9, 1.5 is 3:2, 1.3333 is 4:3, 1.25 is 5:4, 1 is square, 0.8 is 4:5, and 0.5625 is 9:16, the vertical video and story format. A value close to one of these but not exact usually means a crop that drifted by a few pixels; the aspect ratio calculator gives exact dimensions for a target ratio.
Using the numbers on a web page
Put the natural dimensions in the width and height attributes of the <img> tag, even when CSS scales the image: browsers use them to reserve a box of the right shape before the file arrives, which stops the page from jumping as it loads. If the natural width is far more than twice the width the image is displayed at, the file is heavier than any screen needs, and resizing it will speed up the page.
How to use it
- Choose an image.
- Inspect it locally.
- Review the dimension and file facts.
Privacy & limitations
No upload occurs. The reported MIME type comes from the local file and browser decoder.
Related tools
Frequently asked questions
What are natural dimensions?
They are the original decoded pixel width and height, independent of how a page might display the image.
How are megapixels calculated?
Width multiplied by height, divided by one million.
Free tool · runs in your browser · no account required