16OC does real feet-inch-fraction math plus right-angle & rafter solutions, stairs, area & volume, roofing, materials and trig.
It's a free Progressive Web App — no signup, no ads, no subscription. Tap your browser's Share → Add to Home Screen (iOS) or Install app (Android) to get an icon that launches full-screen and works offline.
The screen stays awake while the app is open, so it won't sleep between measurements.
v1.1 · 16oc.pages.dev
Scan to open the free 16OC calculator. Print it and tape it on the job trailer or toolbox so the whole crew can grab it.