Design calculators

Reach-for-them-twice-a-day utilities for designers and front-end developers. Each tool runs entirely in your browser and is optimised to be readable on a phone — useful when a question arrives mid-meeting.

Available tools

Aspect ratio calculator
Width and height in, reduced ratio + scaled dimensions + live preview rectangle out.
DPI / PPI calculator
Pixel dimensions × physical size → dots-per-inch. Presets for common phones, monitors, and print sizes.