Calculators

Quick, transparent calculators for math that comes up constantly but isn't worth opening a spreadsheet for — working out a percentage, splitting a bill with tip included, or similar everyday arithmetic. Every result shows the formula used, not just an answer.

Common use cases

Working out what a percentage discount or markup actually costs
Splitting a restaurant bill with tip across a group of people
Checking a percentage increase or decrease between two numbers

Tools

Percentage Calculator

Calculate percentages, percentage change, and percentage difference.

Tip Calculator

Calculate a tip and split the total across any number of people.

Age Calculator

Calculate exact age in years, months, and days between two dates.

Date Calculator

Find the difference between two dates, or add/subtract time from a date.