About this tool
What is DPI and why does it matter?
DPI (dots per inch) determines print quality. 72 DPI is screen-only. 150 DPI is decent for large posters. 300 DPI is professional print quality. A 1200×1200 image at 300 DPI prints at 4×4 inches — crisp and sharp.
What does Bits/Pixel tell me?
It shows compression efficiency. A raw PNG at 24bpp is uncompressed. A typical JPG falls between 1–4 bpp. Lower = more compressed. Very low values (under 0.5) may mean visible quality loss.
How is Aspect Ratio calculated?
By finding the GCD of width and height and simplifying. For example, 1920×1080 → GCD is 120 → ratio is 16:9. We also match it to common known ratios like 4:3, 1:1, 2.39:1 (cinema), etc.
Is my image uploaded anywhere?
Never. Everything runs inside your browser tab using the Canvas API and FileReader. No server, no upload, no storage. Close the tab and the image is gone.