School, finance, health, and everyday tools — 30 free calculators, instant results, no signup required.
School & Math
Full-featured online scientific calculator with trig, log, powers, factorial, and memory functions.
Calculate weighted or unweighted GPA from any number of courses and credit hours.
Find your current grade and what you need on the final to hit your target.
What is X% of Y? X is what % of Y? Percentage change — all in one place.
Add, subtract, multiply, and divide fractions with full step-by-step work.
Solve ax² + bx + c = 0 with discriminant and step-by-step solution shown.
Paste a list of numbers — get mean, median, mode, range, and standard deviation.
Find any side of a right triangle with angles, area, perimeter, and step-by-step work.
Convert numbers to/from scientific notation and do operations with step-by-step work.
Convert length, weight, temperature, volume, speed, area, data, and time units.
Finance & Money
Monthly payment, total interest, and full amortization schedule for any home loan.
Monthly payment and total cost for personal, auto, student, or business loans.
See how your savings grow with monthly contributions and compound interest.
Find your payoff date and how much extra payments save in interest.
Calculate investment growth with reinvested returns and scenario comparisons.
See if you're on track to retire — and what extra contributions you need.
Convert between USD, EUR, GBP, JPY, and 30+ world currencies with indicative rates.
Health & Body
Calculate your Body Mass Index and healthy weight range in US or metric units.
Find your daily calorie needs (TDEE) to lose, maintain, or gain weight.
Find the best bedtime or wake-up time based on 90-minute sleep cycles for better rest.
Everyday Tools
Calculate tip amount, total bill, and split between any number of people.
Find sale price, savings, original price, or discount percentage — 3 ways.
Add or remove tax from any price. Includes all 50 US state tax rates.
Find your exact age in years, months, days — plus zodiac sign and days until birthday.
Find days between two dates, add or subtract days, and calculate future or past dates.
Add or subtract hours and minutes, find time differences, and convert time units.
Generate random numbers, roll dice, flip a coin, or pick randomly from a custom list.
Create strong, secure, random passwords with custom length and character sets.