Công cụ toán học

Calculate permutations nPr and factorials n! for ordered arrangements with formulas and step-by-step work.

Compute mean, median, mode, standard deviation, variance, quartiles, range, and more from any dataset with step-by-step formulas.

Convert raw scores to z-scores and back using z = (x − μ) ÷ σ, with percentile and step-by-step work.

Find the mean, median, and mode of any data set with frequency tables, sorted data, and step-by-step work.

Count significant figures, round to N sig figs, and add, subtract, multiply, or divide with correct precision rules. Enter decimals, trailing zeros, or scientific notation. Free, instant, browser-based.

Calculate percent error, absolute error, relative error, and percent difference between measured and accepted values. Step-by-step formulas for physics and chemistry lab reports. Free, instant, browser-based.

Calculate sample size for surveys, mean estimates, A/B tests, and two-group comparisons. Set confidence level, power, margin of error, and effect size. Step-by-step formulas. Free, browser-based.

Plot data as line, scatter, or bar charts from x,y pairs or separate columns. Enter lab results, calibration curves, or trial data — get an instant SVG chart with axis labels. Free, browser-based.

Graph mathematical functions y = f(x) instantly. Enter expressions like sin(x), x^2, exp(x), or multiple functions — get an SVG plot with axes, grid, and auto-scaling. Free, browser-based.