Math & Numbers
Percentage Calculator
Three modes — pick the one that matches your question.
Quickly solve any percentage problem: find what percent X is of Y, calculate percentage increase or decrease, find the original value before a percentage change, or get what number equals a given percent. All in one free tool.
Calculation Modes
% of a Number
What is 15% of 200? → 30
Percentage Change
What % increase is from 80 to 100? → 25%
Reverse Percentage
30 is what % of 120? → 25%
Instant Results
Answers update as you type.
How to Use
- Select the calculation type you need.
- Enter the numbers in the input fields.
- The result appears instantly below.
FAQ
How do I calculate a 20% discount?▾
Use '% of a Number' mode: 20% of the original price gives the discount amount. Subtract from the original for the final price.
How do I find percentage increase?▾
Use 'Percentage Change' mode: enter the old value and new value to get the % change.
Quick Formulas
- X% of Y = (X/100) × Y
- % change = ((New - Old) / Old) × 100
- X is what % of Y = (X/Y) × 100
More Math & Numbers
Unit Converter
Convert length, weight, temperature, and more
Random Number Generator
Generate random numbers within any range you set
BMI Calculator
Calculate your Body Mass Index with metric or imperial units
Tip Calculator & Bill Splitter
Calculate tip amount and split the bill among any group
Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal
Roman Numeral Converter
Convert numbers to Roman numerals and back (1–3999)
Compound Interest Calculator
Calculate compound interest with year-by-year breakdown
Discount Price Calculator
Find final price, discount percentage, or original price
Statistics Calculator
Calculate mean, median, mode, standard deviation, and more
Prime Number Checker
Check if a number is prime and generate primes up to N
Loan & Mortgage Calculator
Calculate monthly payments, total interest, and full amortization schedule
Aspect Ratio Calculator
Calculate missing width or height from an aspect ratio. Supports 16:9, 4:3, and custom ratios
GPA Calculator
Calculate semester and cumulative GPA from courses, grades, and credit hours
Calorie & BMR Calculator
Calculate your BMR and daily calorie needs based on activity level and goal
Loan EMI Calculator
Calculate monthly EMI, total interest, and repayment for any loan.