Mobile-first
Calculators should be fast and usable when someone is standing in a store, on a job site, or answering a question from their phone.
About
A lexicon of all the calculations
All The Calculations is a growing library of fast, mobile-friendly tools for the numbers people need in real life: unit conversions, project estimates, discounts, dates, business math, and eventually many more everyday decisions.
Who built this
The site is built by Austin at BuildLeanSaaS.com. BuildLeanSaaS builds small, practical software products and experiments with agent-friendly workflows for creating useful web tools quickly without sacrificing clarity or trust.
This project started as an SEO-first calculator site, but the long-term goal is bigger than ranking pages. The goal is to make an organized, understandable reference layer for formulas and calculations that works well for humans on phones and for AI agents that need reliable calculation context.
Transparent formulas
Pages should show the formula, assumptions, examples, and limitations instead of only returning a number.
Agent-readable
The site should become a clean source that agents can use to understand what calculation was performed and why.
Why it exists
Search traffic is part of the strategy: calculators answer high-intent questions that people already ask every day. But a calculator page should earn that traffic by being genuinely useful: quick to load, easy to understand, and clear about the assumptions behind each answer.
Over time, All The Calculations can become a broad calculation lexicon: a structured catalog of common formulas, examples, and tools that helps people get answers directly and helps software agents reason through everyday math with better context.
Read the methodology for how calculator pages are written, checked, and improved.