Tools & Converters
Encoding, passwords, networks, travel, and handy quick tools.
16 free calculators in this category — all run in your browser.
Password GeneratorGenerate a strong password locally with cryptographic randomness and customizable character sets.Dice RollerRoll one or more secure random dice with a customizable number of sides.Base64 Encode / DecodeEncode or decode UTF-8 Base64 text entirely in your browser.URL Encode / DecodePercent-encode text for a URL or decode an encoded component.Roman Numeral ConverterConvert whole numbers to canonical Roman numerals and back.IP Subnet CalculatorCalculate IPv4 network, broadcast, subnet mask, and host range from a CIDR prefix.Bandwidth CalculatorEstimate how long a file transfer takes at a given connection speed.GDP CalculatorEstimate nominal GDP with the expenditure approach and an optional per-person result.Gas Mileage CalculatorCalculate MPG, L/100 km, fuel cost, and cost per mile from a trip.Mileage CalculatorCalculate trip distance from starting and ending odometer readings.Height CalculatorConvert feet and inches into centimeters, meters, and total inches.Shoe Size ConverterEstimate shoe sizes across US, UK, and EU systems from foot length.Bra Size CalculatorEstimate a starting band and cup size from underbust and bust measurements.Tire Size CalculatorCalculate tire sidewall, overall diameter, circumference, and optional speedometer difference.Golf Handicap CalculatorEstimate a handicap index from round score differentials.Love CalculatorA playful, stable name-pair score for entertainment only.