All Calculators

Every free tool on Calculator Wizard, organized by category. Each one includes the formula, worked examples, and answers to common questions. No account needed for any of them.

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

Discount Calculator

Sale price, savings, and how stacked discounts really work.

Markup Calculator

Selling price and profit from cost, plus markup vs. margin.

Sales Tax Calculator

Tax amount and total from a price and tax rate.

Tip Calculator

Tip amount, total, and split evenly across a group.

School

Grade Percentage Calculator

Test and assignment scores, with a letter grade reference.

GPA Guide

Convert percentage grades to GPA, including weighted GPA.

Math & Statistics

Permutations Calculator (nPr)

Ways to arrange items when order matters, with hover definitions.

Combinations Calculator (nCr)

Ways to choose items when order doesn't matter, with hover definitions.

Loans & Mortgage

Debt Payoff Planner

The biggest tool here. All your debts together — real debt-free date, five payoff strategies compared, and progress tracking. English & Spanish.

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.

Investing & Savings

Investment Growth Calculator

See how an initial investment plus monthly contributions compounds over time.

Compound Interest Guide

The formula behind compounding, explained step by step.

Health

Body Fat Percentage Calculator

Estimate body fat using the U.S. Navy circumference method.

Traditional Calculators

Basic & Scientific Calculator

Standard arithmetic plus trig, logs, exponents, and more.