All Calculators
Every free tool on Calculator Wizard, organized by category. Each one includes the formula, worked examples, and answers to common questions.
Core Percentage Calculators
Percentage Calculator
What is X% of Y — the foundational percentage calculation.
What Percent Calculator
X is what percent of Y — the reverse calculation.
Percent Change
Percentage increase or decrease from an original value.
Percentage Difference
Compare two values symmetrically, without a fixed baseline.
Percentage Point
Percentage points vs. relative percent change, explained.
Shopping & Money
School
Math & Statistics
Loans & Mortgage
Mortgage Payment Calculator
Monthly principal & interest payment from loan amount, rate, and term.
Mortgage Payoff Calculator
See time and interest saved from extra monthly payments.
Auto Loan Calculator
Monthly car payment and total interest from loan amount and term.
Credit Card Payoff Calculator
Payoff time and interest, including the real cost of minimum payments.
APR vs. Interest Rate
What the two percentages actually mean, and why they differ.
Calculator Wizard