Calculators

Calculate percentages, percentage change, and find what percent one number is of another.

Calculate the exact gap in days, weeks, months, and years between any two dates. Free online tool — great for deadlines, anniversaries, and planning.

Calculate your exact age in years, months, and days from your birthdate. Also shows hours, minutes, and days until your next birthday. Free, no signup required.

Calculate your Body Mass Index (BMI) with metric (cm/kg) or imperial (ft/lbs) units. See your WHO weight category instantly — free, no signup.

Calculate tip amount, total bill, and per-person share for any group. Enter bill amount, choose a tip percentage, set the number of diners — done in seconds.

Calculate weighted GPA on the 4.0 scale from course letter grades and credit hours. Supports A through F with +/- modifiers. Free for students.

Scientific calculator with trigonometry, logarithms, exponents, and memory functions.

Generate cryptographically secure random numbers within any range — unique or with repeats.

Add, subtract, multiply, and divide fractions. Shows simplified result, mixed number, and decimal.

Calculate mean, median, mode, range, variance, and standard deviation from a list of numbers.

Solve any quadratic equation ax² + bx + c = 0. Shows real and complex roots, discriminant, and vertex.

Solve any triangle from three known values. Computes sides, angles, area, perimeter, and height. Supports SSS, SAS, ASA, AAS, and SSA cases.

Calculate radius, diameter, circumference, and area of a circle from any one known value. Also computes sphere surface area and volume.

Solve proportions (A:B = C:D) for any missing value. Simplify ratios, scale ratios, and convert ratios to fractions, decimals, and percentages.

Calculate a missing width or height from any aspect ratio, or reduce a W×H pair to its simplest ratio. Includes presets for 16:9, 4:3, 21:9, and more.

Convert any number to English words — cardinal form, check/cheque-writing format, with title case, lower case, or UPPER options.

Calculate sale price, amount saved, and effective discount %. Supports stacked discounts and optional sales tax for the final out-the-door price.