Tool Belt Logic is the construction calculator built for the trades — framers, concrete crews, carpenters, remodelers, and general contractors. Switch between a clean Plain Calculator for everyday math and a full Construction Mode that works in feet, inches, and fractions and runs the formulas you actually use on the jobsite.

CONSTRUCTION CALCULATOR
Work natively in feet, inches, and fractions down to 1/32. Quick keys for 1/2, 1/4, 1/8, and 1/16. Set your precision from rough framing to finish carpentry and the display rounds to match. Teach the calculator your crew's shorthand — hoof for foot, hair for 1/8, gnat for 1/16, kerf, tick — and it translates as you type.

BUILT-IN FRAMING & TRADE FORMULAS
Roof pitch and slope. Hip and valley with irregular-hip support and cut angles. Rake walls, stud counts, and stair layouts. Circles, triangles, and area with plan and elevation diagrams. Concrete and footing volumes. Board feet and lumber. Tap a formula, fill in what you know, and get the answer plus a diagram you can reference on site.

AI CHAT ASSISTANT
Ask construction math questions in plain English — stud counts, rake walls, stair layouts, footings, lumber, concrete takeoffs — and get worked-through answers without leaving the app. The assistant knows your selected mode and gives trade-aware answers, not generic chatbot replies. AI features are opt-in.

RECALLS, HISTORY & TAPE
Save common values as recalls and pull them back with a tap. Every calculation goes into your history. Tape mode shows your math as a running ribbon you can scroll, share, or repeat with one tap.

WORKS OFFLINE
The calculator and formulas work without a signal. AI chat needs internet; everything else keeps going when service drops. Works in English and Spanish.

PRIVACY YOU CAN ACTUALLY READ
No account required. No name, email, or phone. Your data is tied to an anonymous device ID, not to you. AI features are opt-in and clearly disclosed. History and saved items stay on your device.

Tool Belt Logic by Chill Inc. Built for the trades.