Everyday Calculation Guides
Learn simple methods for calculations that come up in everyday life. These guides explain the formulas and reasoning behind percentages, dates, ages, tips and common measurements.
Browse everyday guides
5 practical guides covering Percentages, age, calendar dates, tipping and everyday volume calculations.
How to Calculate Percentage: Formulas and Examples
Learn how to calculate percentages, percentage change, percentage increase and decrease with simple formulas and examples.
EverydayHow to Calculate Age from Date of Birth
Learn how age is calculated from a date of birth, why birthdays matter, and how to determine years, months and days accurately.
EverydayHow to Calculate the Difference Between Two Dates
Learn how to calculate days between dates and understand calendar differences involving months, years and leap years.
EverydayHow Much Should You Tip? Tip Percentage Guide
Learn how to calculate a tip, split a bill and compare common tip percentages using simple formulas.
EverydayHow to Calculate Volume: Common Shapes and Formulas
Learn how to calculate volume for rectangular boxes, cubes and other common shapes, with units and conversion guidance.
When you are ready to calculate a result, visit our Everyday Calculators for interactive tools related to these guides.