Collections
Hand-picked groups of calculators for specific projects, life events, and disciplines.
Buying a house
Mortgage, affordability, closing costs, property tax — the whole purchase modelled.
Pregnancy & newborn
From due date and ovulation tracking to baby percentile and milk intake.
Marathon training
Pace, splits, VO2 max, race-time predictors — everything for a 26.2 mile build-up.
Home renovation
Estimate paint, flooring, drywall, lumber, concrete and electrical for a remodel.
Personal finance
Budgeting rules, savings goals, retirement projections, credit-card payoff.
Day trading & options
Position sizing, Greeks, option pricing models, risk-reward setup.