Free math calculators for students. Each page has a working calculator, the formula, worked examples and answers to common questions. Pick a topic below, or use the search at the top of the page.
Calculators
Free calculators for algebra, geometry, grades and GPA, number systems, time and statistics, each with the formula and a worked example.
Algebra and functions
Slope Calculator
Find the slope between two points with steps: rise over run, line equation, angle, distance and midpoint. Free…
Standard Form to Slope-Intercept Form Calculator
Convert Ax + By = C to y = mx + b with steps. Shows the slope, y-intercept…
Square Root Calculator
Find the square root of any number with simplified radical form, nearby perfect squares and steps. Free square…
Geometric Series Calculator
Find the nth term and the sum of a geometric series from the first term, ratio and number…
Intersection of Two Lines Calculator
Find where two lines cross, or whether they are parallel or the same line. Enter y = mx…
Percentage Increase Calculator
Find the percent change between two numbers, or increase or decrease a number by a percent. Free percentage…
Geometry
Isosceles Triangle Calculator
Find the area, perimeter, height and angles of an isosceles triangle from its base and sides, base and…
Heron’s Formula Calculator
Find the area of a triangle from its three side lengths with Heron's formula. Also shows the semi-perimeter,…
Distance From a Point to a Line Calculator
Find the shortest distance from a point to a line given as Ax + By + C =…
Equation of a Circle Calculator
Write the equation of a circle from its center and radius, or find the center and radius from…
Perimeter Calculator
Find the perimeter and area of a rectangle, square, triangle or circle. Enter the sides and get both…
Grades and GPA
Test Score Calculator
Find your test score as a percent and letter grade, and see how many points you need to…
GPA Calculator
Calculate your semester and cumulative GPA from letter grades and credits on a 4.0 scale. Free GPA calculator…
Weighted Grade Calculator
Calculate your weighted grade from scores and weights, and find the score you need on the final exam.…
Number systems
Place Value Calculator
Break any number into place values, find the digit in the ones, tens, thousands, tenths or hundredths place,…
Binary Calculator
Add, subtract, multiply and divide binary numbers with decimal checks and steps. Free binary calculator.
Binary to Decimal Converter
Convert binary to decimal, or convert between binary, decimal, octal and hexadecimal, with the working shown.
LCM and GCF Calculator (Also Finds the LCD)
Find the least common multiple and greatest common factor of 2 to 6 numbers, or the least common…
Boolean Algebra Calculator
Evaluate and simplify a Boolean expression with a full truth table, minterms, maxterms and a simplified sum of…