Study & statistics
Understand the numbers behind your work. Work stays in your browser tab.
Weighted grade calculator
Calculate a grade from assessment scores and weights.
GPA calculator
Calculate credit-weighted grade points on a supplied scale.
Final exam score needed
Find the final exam score needed to reach your target.
Fraction simplifier
Reduce an integer fraction using the greatest common divisor.
Quadratic equation solver
Find real or complex roots of ax² + bx + c = 0.
Standard deviation calculator
Show sample and population standard deviation.
Median and mode calculator
Find median values and all repeated modes.
Quartile calculator
Compute quartiles using median-of-halves, excluding an odd median.
Z score calculator
Standardize a value against a mean and nonzero SD.
Confidence interval calculator
Estimate a 95% normal interval for an independent sample mean.
Pearson correlation
Measure linear correlation between paired numeric observations.
Linear regression
Fit an ordinary least-squares straight line.
Permutation calculator
Compute nPr exactly for bounded nonnegative integers.
Combination calculator
Compute nCr exactly for bounded nonnegative integers.
Study time planner
Divide study time across subjects using priority weights.