Best Free Online Calculators for Students in 2026
Why Online Calculators Beat Physical Ones
Online calculators are always in your pocket (via smartphone), never need batteries, are far more specialized than a generic calculator, and many show their work step-by-step — invaluable for learning. Here are the most useful calculators for students at every level.
GPA Calculator
Calculate your semester GPA or cumulative GPA by entering your grades and credit hours. Essential at semester end to understand your standing and plan ahead. Most universities calculate GPA on a 4.0 scale where A=4.0, B=3.0, C=2.0, D=1.0. Use our free GPA Calculator.
Percentage Calculator
Instantly calculate percentages for test scores, grade calculations, discount problems, and statistics assignments. Three common operations: "what is X% of Y?", "X is what percent of Y?", and "X is Y% of what?" Use our free Percentage Calculator.
Scientific Calculator
Handle trigonometry, logarithms, exponents, factorial, and statistical functions. Essential for science, math, engineering, and economics coursework. Use our free Scientific Calculator.
Fraction Calculator
Add, subtract, multiply, and divide fractions with full working shown. Automatically simplifies results to lowest terms. Useful for arithmetic, pre-algebra, and any calculation involving mixed numbers. Use our free Fraction Calculator.
Prime Number Checker
Instantly determine whether any number is prime, find all prime factors, and generate lists of prime numbers up to N. Useful for number theory, cryptography coursework, and competition math. Use our free Prime Number Checker.
Number Base Converter
Convert between binary, octal, decimal, and hexadecimal. Essential for computer science courses covering data representation, digital logic, and assembly programming. Use our free Number Base Converter.
BMI Calculator
Calculate Body Mass Index for health and physical education classes. Understand the BMI formula and its limitations as a health screening tool. Use our free BMI Calculator.
Compound Interest Calculator
Model investment growth over time for economics and personal finance classes. Understand the power of compounding with different rates, frequencies, and time horizons. Use our free Compound Interest Calculator.