All Unit Conversions
Apex Conversion covers 20 measurement categories — from everyday units like length and weight to specialized tools for pressure, electrical, typography, and currency. Every tool is free, requires no account, and works on any device.
Length
Convert between meters, feet, inches, kilometers, miles, yards, nautical miles, and more.
Weight
Switch between pounds, kilograms, grams, ounces, stones, milligrams, and metric tonnes.
Temperature
Convert between Celsius, Fahrenheit, and Kelvin instantly with the correct formulas.
Volume
Convert liters, gallons, cups, fluid ounces, milliliters, tablespoons, teaspoons, and more.
Area
Convert square feet, acres, hectares, square meters, square miles, and more.
Speed
Convert miles per hour, km/h, knots, meters per second, and feet per second.
Time
Convert milliseconds, seconds, minutes, hours, days, weeks, months, and years.
Data Storage
Convert bits, bytes, kilobytes, megabytes, gigabytes, terabytes, petabytes, and binary units (KiB, MiB, GiB, TiB).
Energy
Convert joules, kilocalories, kilowatt-hours, BTUs, electronvolts, and more.
Pressure
Convert between PSI, bar, atmospheres, pascals, kilopascals, millimeters of mercury, torr, and inches of mercury.
Fuel Economy
Convert MPG (US and UK), km/L, and L/100km — the three dominant fuel efficiency standards worldwide.
Currency
Convert between major world currencies with static reference rates. For live rates, always check your bank or a financial data provider.
Cooking
Convert cups, tablespoons, teaspoons, milliliters, fluid ounces, and sticks of butter for any recipe.
Shoe Size
Convert shoe sizes between US Men's, US Women's, UK, EU, and foot length in centimeters.
Typography
Convert between px, rem, em, pt, pica, and print units for CSS and digital design. Based on 96 dpi screen resolution.
Electrical
Convert millivolts to volts, milliamps to amps, watts to kilowatts, and ohms to kilohms. Select compatible units — cross-quantity conversions show Ohm's law reference.
Number Scale
Convert between SI magnitude prefixes — pico, nano, micro, milli, kilo, mega, giga, tera, and peta. Essential for scientific and engineering work.
Bitrate
Convert between bps, Kbps, Mbps, Gbps, and byte-per-second rates. Understand network speeds and file transfer times.
Angle
Convert between degrees, radians, gradians, arcminutes, arcseconds, and full turns for geometry, navigation, and engineering.
Frequency
Convert between Hz, kHz, MHz, GHz, RPM, and rotations per second for audio, radio, electronics, and mechanical systems.
How Conversions Work
Every conversion on this site uses a fixed mathematical relationship between units. For example, one inch is always exactly 2.54 centimeters, and one kilogram is always 1,000 grams. These relationships are defined by international standards and do not change.
Temperature conversions (like Celsius to Fahrenheit) use a formula rather than a simple multiplier, because the scales start at different zero points. The formula is applied automatically when you enter a value.
Results are rounded to a reasonable number of decimal places for everyday use. If you need higher precision for scientific or engineering work, please verify results with a professional-grade tool or reference material.