Tools · free conversion utilities
Eleven mobile-first conversion tools · zero login, zero ads. Each tool gives a one-glance answer plus a brief educational note explaining the underlying logic.
Numbers
Numeric format converters · Roman numerals, base, scientific notation, fractions.
Ⅻ
Roman Numerals
Convert between decimal numbers and Roman numerals · 1 through 3999, with additive and subtractive logic shown.
01
Base Converter
Live conversion between binary, decimal, hexadecimal, and octal · type in any field and the others update.
×10ⁿ
Scientific Notation
Convert any decimal to scientific or engineering notation · exponents in multiples of 3 for engineering style.
½
Fraction · Decimal · Percent
Three-way conversion · automatic GCD reduction, mixed-number support, percent display.
Time & Space
Calendar, clock, and map utilities · time zones, date math, distance, coordinates.
🕐
Time Zone Converter
Convert times across cities · automatic DST handling, shareable links for cross-zone meetings.
📆
Date Calculator
Duration between two dates, add or subtract days, exclude weekends, presets for 7 / 30 / 90 / 100-day milestones.
📏
Distance Between Cities
Great-circle (Haversine) distance between any two latitude/longitude pairs · returns kilometres, miles, and the cardinal bearing.
🧭
Coordinate Converter
Convert decimal degrees (DD) to degrees-minutes-seconds (DMS) · one-click open in Google Maps or OpenStreetMap.
📍
Lat/Long Finder
Look up latitude and longitude from a city name · or paste coordinates and get the city back. Works fully offline against a built-in city table.
Reference
Day-to-day reference converters · temperature, cooking measurements.
