Math & Utility Calculators

Algebra solvers, geometry tools, number system converters, and developer utilities. Fast, free, and works offline.

Core Math

Percentage Calculator

Three tools in one: find X% of Y, what percent X is of Y, and percentage change.

Scientific Calculator

Trig, logs, exponents, factorials, and more.

Fraction Calculator

Add, subtract, multiply, and divide fractions.

Exponent Calculator

Calculate powers, roots, and work with exponent rules.

Logarithm Calculator

Natural log, common log, and custom base logarithms.

Ratio Calculator

Solve proportions, simplify ratios, and scale values.

Decimal to Fraction

Convert decimals to simplified fractions and back.

Algebra & Geometry

Quadratic Equation

Solve ax² + bx + c = 0 with real or complex roots.

Pythagorean Theorem

Find the missing side of a right triangle.

Area Calculator

Calculate area for 7 shapes: rectangle, circle, triangle, and more.

Square Footage

Calculate area for rooms, floors, and walls.

Statistics

Standard Deviation

Calculate standard deviation, variance, mean, and more.

Average Calculator

Find mean, median, mode, range, and sum of any data set.

Random Number Generator

Generate random numbers, roll dice, or flip coins.

Number Systems & Conversion

Binary Calculator

Binary arithmetic and conversion to/from decimal, hex, octal.

Hex Converter

Convert hexadecimal to decimal, binary, and octal.

Roman Numeral Converter

Convert between Roman numerals and Arabic numbers.

Unit Converter

Convert length, weight, volume, temperature, and more between metric and imperial.

Date, Time & Education

Date Calculator

Find the difference between two dates or add/subtract days from a date.

GPA Calculator

Calculate your semester and cumulative GPA on a 4.0 scale.

Grade Calculator

Weighted grade average and “what do I need on the final” solver.

Text & Developer Tools

Word Counter

Count words, characters, sentences, and reading time.

Text Case Converter

Convert text to uppercase, lowercase, title case, and more.

JSON Formatter

Format, validate, and minify JSON data.

Color Converter

Convert between HEX, RGB, HSL, and CMYK color formats.

Password Generator

Create strong, random passwords with custom rules.

Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes.

Byte Converter

Convert between bytes, KB, MB, GB, TB, and more.

IP Subnet Calculator

Calculate network address, broadcast, and usable host range.

QR Code Generator

Create QR codes for URLs, text, Wi-Fi, and contacts.

Countdown Timer

Set a countdown to any future date or event.

Timezone Converter

Convert times between 400+ world time zones.

When to Use These Calculators

The Percentage Calculator handles the three most common percentage questions: finding a percentage of a number, figuring out what proportion one number is of another, and calculating percentage increase or decrease. It’s useful for discounts, tax calculations, grade conversions, and data analysis.

The Unit Converter covers length, weight, volume, temperature, area, and speed — handy for cooking, travel, science homework, or international shopping.

Use the Date Calculator for project deadlines, age calculations, or counting days between events. The GPA Calculator supports standard 4.0 scale grading with credit hour weighting.

Need financial tools? Visit our Financial Calculators. For health-related tools, see Health Calculators.