Images are measured in your browser and never uploaded.
How to find the size of an image
Drop an image onto the box above, choose it from your device, or copy an image and press Ctrl+V (Cmd+V on a Mac). You'll immediately see its exact width and height in pixels, megapixels, aspect ratio, file size, and how big it measures in inches, centimeters, and millimeters. You can measure a whole folder of images at once and download the results as a CSV spreadsheet.
Dimensions are read straight from the file's header, so the numbers are exact, and it works even for formats your browser can't display, like HEIC photos from an iPhone, TIFF scans, and Photoshop files.
Pixels are the real size. Inches depend on you.
An image file only really has one size: its width and height in pixels. Inches and centimeters only exist once you decide how densely to print those pixels, measured in pixels per inch (ppi, often called DPI). The same 3000 × 2000 pixel photo prints at 10 × 6.7 inches at 300 ppi, or 20 × 13.3 inches at 150 ppi.
Many files carry a DPI number in their metadata, often 72 or 96, but it's only a suggestion that most programs ignore. It doesn't change the image. That's why this tool lets you pick the print resolution and shows the file's own DPI separately.
| Resolution | What it's good for |
|---|---|
| 300 ppi | Photo prints, books, and anything viewed up close. The standard for sharp printing. |
| 200–240 ppi | Good-quality prints where 300 isn't possible. Most people can't tell the difference at arm's length. |
| 150 ppi | Posters and large prints viewed from a few feet away. |
| 72–100 ppi | Banners and signs viewed from across a room. Too low for anything handheld. |
Why a photo's width and height look swapped
Phones and cameras usually save the sensor image sideways and add an orientation tag telling apps to rotate it. A portrait iPhone photo may be stored as 4032 × 3024 but shown as 3024 × 4032. This tool detects the tag and reports the size as you see it, noting the stored size when the two differ. If an upload form rejects a photo for being the wrong orientation, this is usually why.
Aspect ratio and common sizes
The aspect ratio is the shape of the image: width divided by height. It's shown as a simple ratio like 4:3 or 16:9, and when the exact ratio is awkward (1366 × 768 is really 683:384) the tool shows the nearest standard ratio too. It also recognizes common exact sizes, such as 1920 × 1080 (Full HD), 1080 × 1350 (Instagram portrait), and 1200 × 630 (the size used for link previews on social media).
Frequently asked questions
How do I check image dimensions on Windows or Mac without a tool?
On Windows, right-click the file, choose Properties, then the Details tab. On a Mac, select the file in Finder and press Cmd+I, or open it in Preview and choose Tools, then Show Inspector. Neither accounts for rotated phone photos the way this tool does, and neither handles many files at once.
What's the difference between image size and file size?
Image size usually means dimensions: how many pixels wide and tall. File size is how much storage it takes, in KB or MB. A large image can have a small file size if it's compressed heavily, and a small image saved as uncompressed BMP or TIFF can be huge. Both are shown here.
How many megapixels do I need for a print?
Multiply the print size in inches by 300 to get the pixels needed for a sharp print. A 4 × 6 inch print needs 1200 × 1800 pixels (about 2.2 megapixels), and an 8 × 10 needs 2400 × 3000 (7.2 megapixels). Each image card here lists the largest sizes it can print at 300, 200, and 150 ppi.
Does changing the DPI make an image bigger or sharper?
No. Changing the DPI setting only changes the suggested print size. To get more detail you need more pixels, and enlarging an image with software only stretches the pixels it already has.
Why does it say my photo contains location data?
Phones and many cameras save the GPS coordinates where a photo was taken inside the file. If you share the original file, others can read that location. Most social networks remove it when you upload, but email, messaging apps, and file-sharing links often don't.
How is an SVG measured?
SVG files are vector graphics, so they scale to any size without losing quality. The tool reports the size the file asks to be displayed at, from its width, height, or viewBox. That's a default size, not a limit.