Math Calculators
Fast answers for everyday math — percentages three ways and a credit-weighted GPA. Type the numbers, get the result, and see the exact formula we used.
Both tools show their working. The percentage calculator prints the formula with your numbers in it, and the GPA calculator lists the credits and grade points behind the average, so you can check homework, a transcript or a price yourself instead of trusting a single number.
How to choose the right calculator
You have a percentage and a number
To find a discount, a tip or a commission, use the X% of Y mode of the percentage calculator: for example, 20% of 225.
You have a part and a whole
To turn a score or a share into a percentage, use the What percent mode of the percentage calculator: for example, 42 out of 48.
You have an old value and a new one
To measure growth or decline, such as a price, rent or salary from one year to the next, use the Percent change mode of the percentage calculator. It labels the result as an increase or a decrease and shows the difference.
You have grades and credit hours
To average grades the way schools do, weighting each course by its credits, use the GPA calculator. Enter one semester for a term GPA, or every course you have taken for a cumulative GPA.
Guide to each calculator
Percentage Calculator
Answers the three everyday percentage questions in one place. Choose a mode: X% of Y takes a percentage and a value, What percent takes a part and a whole, and Percent change takes a starting value (A) and an ending value (B). You get the result, the inputs it used and the formula with your numbers filled in; the percent change mode also shows the difference between the two values and whether it is an increase or a decrease. Percent change is measured against the starting value, which is why a rise and a fall of the same amount give different percentages. Open the percentage calculator.
GPA Calculator
Answers what your grade point average is on the standard 4.0 scale. Add a row for each course with its name, credit hours and letter grade from A+ to F, and remove rows you do not need. You get the weighted GPA to two decimals, the number of courses, total credit hours, total grade points and a general academic standing label. Because each grade is weighted by its credits, a 4-credit course moves the average more than a 1-credit lab, and a cumulative GPA is not the simple average of semester GPAs. Schools that use honors weighting or a different scale may report a different official GPA. Open the GPA calculator.
Checking the math yourself
Every percentage problem comes down to one relationship: part equals percent divided by 100, times the whole. The three modes rearrange that relationship to solve for the missing piece. A GPA is a weighted average: multiply each grade's points by its credits, add those products, and divide by the total credits. Both calculators keep full precision while they work and only round the number they display, so results do not drift when you change one input at a time.
Rounding and display
The percentage calculator shows up to four decimal places so you can round to whatever your teacher, receipt or report requires. The GPA is shown to two decimals, which is how most transcripts report it, but a school may round or truncate differently at the cut-off for honors or scholarships, so check its own rules when you are close to a threshold.
About our math calculators
Percentages and grade averages come up constantly, from discounts and test scores to transcripts and scholarship cut-offs. Our math calculators do the arithmetic at full precision, show the answer immediately, and then walk through the formula with your own numbers so you can check the work or learn the method. There is nothing to install and nothing to sign up for.