Calculators & Converters

Solve common percentage questions, including a percentage of a number, percentage change, reverse percentages, ratios, differences, and markups.

Create downloadable QR codes for URLs, text, contact details, Wi-Fi credentials, email, phone, SMS, locations, and other common content types.

Calculate exact age in calendar years, months, and days, plus totals and the time remaining until the next birthday.

Create one or five random passwords with configurable length, character sets, required characters, and exclusions.

Convert values across length, mass, temperature, area, volume, speed, time, storage, pressure, energy, power, angle, fuel economy, force, and frequency.

Measure the interval between dates, add or subtract calendar time, count weekdays, or calculate days until or since a target date.

Generate secure random integers or decimals, pick or shuffle list items, and make Yes/No or coin-flip selections.

Convert conventional Roman numerals to decimal integers or turn integers from 1 through 3999 into canonical Roman notation.