Free online calculators — math, date/time, and academic calculators for percentages, fractions, date differences, grade averages, and more. 100% browser-based.
Online calculators for math, date/time, and academic calculations — percentages, fractions, quadratic equations, date differences, grade averages, and more. Every calculation runs in your browser with nothing sent to a server. No sign-up, no data collection, just fast, accurate results.
Computes percentage values, percentage increases and decreases, and what-percent-of-what relationships with precise decimal arithmetic. Essential for everyday math — tips, discounts, tax rates, grade scores, and statistical comparisons where quick percentage answers are needed.
Calculate base raised to an exponent power. Compute large exponential values quickly with this simple math tool. Everything runs locally in your browser — nothing is uploaded.
Add, subtract, multiply, and divide fractions. Get simplified results for all common fraction arithmetic operations. Everything runs locally in your browser — nothing is uploaded.
Convert fractions to decimal numbers. Shows the step-by-step division process. Everything runs locally in your browser — nothing is uploaded.
Simplify ratios to their lowest terms. Enter two numbers to find the simplest whole-number ratio between them. Everything runs locally in your browser — nothing is uploaded.
Calculate probability of an event occurring. Enter favorable outcomes and total outcomes to get probability percentage and odds. Everything runs locally in your browser — nothing is uploaded.
Calculate the number of ways to choose k items from n items (nCr). Includes the formula and step-by-step result. Everything runs locally in your browser — nothing is uploaded.
Check if any number is prime. Also shows all factors and whether the number is odd or even. Everything runs locally in your browser — nothing is uploaded.
Calculate the GCF/GCD of two or more numbers. Shows the prime factorization method step by step. Everything runs locally in your browser — nothing is uploaded.
Calculate the remainder of division (a mod b). Shows quotient, remainder, full division expression, and negative dividend semantics. Everything runs locally in your browser — nothing is uploaded.
Calculate mean, median, and mode from a list of numbers. Statistical analysis for any dataset with instant results. Everything runs locally in your browser — nothing is uploaded.
Solve quadratic equations of the form ax² + bx + c = 0. Get real and complex roots with step-by-step solutions. Everything runs locally in your browser — nothing is uploaded.
Calculate circle area and circumference from radius. Quick geometry calculations for circles of any size. Everything runs locally in your browser — nothing is uploaded.
Calculate the aspect ratio from width and height dimensions. Find the simplified W:H ratio for images, videos, and screens. Everything runs locally in your browser — nothing is uploaded.
Calculate dots per inch from pixel dimensions and physical size. Determine display and print resolution quality. Everything runs locally in your browser — nothing is uploaded.
Evaluate mathematical expressions with sin, cos, tan, log, and sqrt functions. A versatile scientific calculator in your browser. No signup or account required.
Convert between degrees and radians. Shows the formula and step-by-step conversion process. Everything runs locally in your browser — nothing is uploaded.
Round numbers to a specified number of significant figures. Essential for scientific and engineering calculations. Everything runs locally in your browser — nothing is uploaded.
Calculate fuel economy in MPG (miles per gallon) from distance driven and fuel consumed. Everything runs locally in your browser — nothing is uploaded.
Calculate the percentage difference between any two numbers. Useful for comparing data sets, prices, and measurements. Everything runs locally in your browser — nothing is uploaded.
Solve algebraic expressions, evaluate formulas, and simplify expressions. Perfect for homework and quick calculations. Everything runs locally in your browser — nothing is uploaded.
Calculate area, perimeter, and volume for shapes including circle, square, triangle, rectangle, sphere, cylinder, cone, and cube. Everything runs locally in your browser — nothing is uploaded.
Calculate the slope, equation, and intercept of a line from two points. Shows the full line equation in y = mx + b form. Everything runs locally in your browser — nothing is uploaded.
Solve linear and quadratic equations. Enter an equation with one variable (x) and see the step-by-step solution. Everything runs locally in your browser — nothing is uploaded.
Calculate width, height, and area from diagonal screen size and aspect ratio.
Solve proportions with three known values. Find the missing value in a:b = c:d ratio equations. Everything runs locally in your browser — nothing is uploaded.
Calculate pixels per inch from diagonal resolution and screen size. Determine screen sharpness and pixel density. Everything runs locally in your browser — nothing is uploaded.
Calculate the hypotenuse of a right triangle using the Pythagorean theorem. Enter sides a and b to find side c. Everything runs locally in your browser — nothing is uploaded.
Calculate the area and perimeter of a rectangle from length and width. Simple geometry for construction, design, and planning. Everything runs locally in your browser — nothing is uploaded.
Calculate the square root of any number. Get precise square root values for mathematical and scientific calculations. Everything runs locally in your browser — nothing is uploaded.
Calculate standard deviation, variance, and mean from a list of numbers. Statistical analysis for data science and mathematics. Everything runs locally in your browser — nothing is uploaded.
Convert decimal numbers to fractions. Handles terminating and repeating decimals with precision. Everything runs locally in your browser — nothing is uploaded.
Calculate the number of ways to arrange k items from n items (nPr). Shows the step-by-step permutation calculation. Everything runs locally in your browser — nothing is uploaded.
Calculate the factorial of any number (n!). Handles large numbers and shows the full multiplication sequence. Everything runs locally in your browser — nothing is uploaded.
Find the prime factors of any number. Shows the complete factorization tree and exponential form. Everything runs locally in your browser — nothing is uploaded.
Calculate the LCM of two or more numbers. Shows the prime factorization approach for clarity. Everything runs locally in your browser — nothing is uploaded.
Calculate logarithms with any base. Supports log base 10, natural log (ln), and custom bases. Everything runs locally in your browser — nothing is uploaded.
Calculate sine, cosine, tangent, and their inverses. Enter an angle in degrees or radians and see all six trig functions. Everything runs locally in your browser — nothing is uploaded.
Convert numbers between standard form and scientific notation (E-notation). Handles very large and very small numbers. Everything runs locally in your browser — nothing is uploaded.
Round numbers using 5 modes: round half up, banker's rounding, floor, ceil, and truncate. Shows step-by-step explanation with the digit being rounded. Everything runs locally in your browser — nothing is uploaded.
Calculate the distance and midpoint between two points on a 2D coordinate plane. Everything runs locally in your browser — nothing is uploaded.
Calculate the area of a triangle given base and height using the formula 0.5 × base × height. Everything runs locally in your browser — nothing is uploaded.
Computes exact age in years, months, and days from a given birth date relative to any target date. Everything runs locally in your browser — nothing is uploaded.
Count the number of business days between two dates, excluding weekends. Plan projects and track working days accurately. Everything runs locally in your browser — nothing is uploaded.
Find out what day of the week any date falls on. Look up birthdays, holidays, historical events, and future dates. Everything runs locally in your browser — nothing is uploaded.
Calculate the day number of the year for any date. Find out which day of 365 (or 366) a specific date represents. Everything runs locally in your browser — nothing is uploaded.
Check if any year is a leap year. Enter a year to find out if it has 366 days with February 29. Everything runs locally in your browser — nothing is uploaded.
Calculate the exact days, hours, and minutes remaining until a specified future date and time. Everything runs locally in your browser — nothing is uploaded.
Calculate the exact difference between two dates in days, hours, minutes, and seconds. Perfect for project timelines and countdowns. Everything runs locally in your browser — nothing is uploaded.
Find the ISO week number for any date. Also shows the day of the week and the current week of the year. Everything runs locally in your browser — nothing is uploaded.
Calculate total work hours between start and end times with a configurable break. Essential for timesheets and payroll. Everything runs locally in your browser — nothing is uploaded.
Estimate travel time from distance and speed — with optional arrival time.
Calculate the exact duration between two times. Handles overnight time spans and displays results in hours, minutes, and seconds. Everything runs locally in your browser — nothing is uploaded.
Add or subtract hours and minutes from a starting time. Perfect for scheduling, project planning, and time tracking. Everything runs locally in your browser — nothing is uploaded.
Plan meeting times across multiple timezones. Select date and time, then see the equivalent time in all selected cities simultaneously. Everything runs locally in your browser — nothing is uploaded.
Add or subtract days from any date. Get the resulting date instantly — useful for deadlines, scheduling, and planning. Everything runs locally in your browser — nothing is uploaded.
Calculate the time elapsed between any date and now. Shows results in years, months, weeks, days, hours, minutes, and seconds. Everything runs locally in your browser — nothing is uploaded.
Check when daylight saving time starts and ends in the US for any year. Shows the exact dates and DST period length. Everything runs locally in your browser — nothing is uploaded.
Add, subtract, and calculate duration between hours and minutes. Perfect for time tracking and scheduling. Everything runs locally in your browser — nothing is uploaded.
Calculate your final grade using weighted assignment scores. Enter grades and their weights to compute your overall percentage. Everything runs locally in your browser — nothing is uploaded.
Calculate your Grade Point Average from letter grades and credit hours. Supports standard 4.0 grading scale. Everything runs locally in your browser — nothing is uploaded.
Convert percentage scores to letter grades. Enter your percentage to see the corresponding letter grade on standard scale. Everything runs locally in your browser — nothing is uploaded.
Calculate semester and cumulative GPA. Enter current grades, credits, and previous GPA to track your academic performance. Everything runs locally in your browser — nothing is uploaded.
Calculate total study hours over a period and see monthly projections.
Convert correct/total answers to percentage and letter grade.
Estimate how many pages your word count will take at different font sizes.