Unit Converter

Convert between metric and imperial units for length, weight, and temperature with high precision.

Convert Units

→

Complete Unit Conversion Guide

Unit conversion is one of the most frequent calculations people perform in daily life and professional work. Whether you're a student solving physics problems, an engineer reviewing blueprints from different countries, a cook following a recipe from abroad, or a traveler navigating speed limits and distances in unfamiliar units, the ability to convert between measurement systems is an essential skill.

Our Unit Converter covers three essential measurement categories: Length, Weight, and Temperature — the most commonly converted unit types in everyday use.

Length Conversions

The world uses two primary length systems: the metric system (International System of Units, SI), used by the majority of countries worldwide, and the imperial system, used primarily in the United States, Liberia, and Myanmar for everyday measurements.

Key length relationships:

  • 1 meter (m) = 100 centimeters = 1,000 millimeters
  • 1 kilometer (km) = 1,000 meters = 0.621371 miles
  • 1 inch (in) = 2.54 centimeters
  • 1 foot (ft) = 12 inches = 30.48 centimeters
  • 1 yard (yd) = 3 feet = 0.9144 meters
  • 1 mile (mi) = 5,280 feet = 1.60934 kilometers

Weight Conversions

Weight and mass conversions are critical in cooking, shipping, medicine, fitness, and science. The key distinction between weight and mass is often blurred in everyday language — we use both terms interchangeably in common usage, though scientifically they're different (mass is an intrinsic property; weight is a force dependent on gravity).

  • 1 kilogram (kg) = 1,000 grams = 2.20462 pounds
  • 1 pound (lb) = 16 ounces = 453.592 grams
  • 1 ounce (oz) = 28.3495 grams
  • 1 metric ton = 1,000 kg = 2,204.62 pounds
  • 1 stone (UK) = 14 pounds = 6.35029 kg

Temperature Conversions

Temperature is measured in three scales in common use: Celsius (°C), used in most countries; Fahrenheit (°F), used primarily in the United States; and Kelvin (K), the SI base unit used in scientific contexts.

Conversion formulas:

°F = (°C × 9/5) + 32
°C = (°F – 32) × 5/9
K = °C + 273.15

Common reference temperatures: Water freezes at 0°C / 32°F / 273.15K. Water boils at 100°C / 212°F / 373.15K. Normal human body temperature is 37°C / 98.6°F / 310.15K.

Frequently Asked Questions

Our converter uses standard scientific conversion factors with up to 6 significant figures of precision. For everyday purposes, this level of precision is more than adequate. For scientific or engineering work requiring greater precision, always refer to primary metrology standards from NIST or BIPM.
Yes, the tool handles a wide range of numeric inputs. For extremely small numbers (nano/micro scale) or extremely large ones (astronomical), scientific notation is supported as input in some browsers' number fields. Results are displayed in standard decimal notation up to 6 decimal places.
We've focused on the most commonly needed everyday units. Specialized units like nautical miles, fathoms, furlongs, or light-years serve niche audiences. We may expand the tool in future updates. For highly specialized scientific conversions, dedicated scientific tools or unit conversion libraries are recommended.
The most common mistake is confusing the direction of conversion — dividing when you should multiply. For example, to convert centimeters to inches, you divide by 2.54. To convert inches to centimeters, you multiply by 2.54. Our tool eliminates this confusion by handling the direction automatically based on your From/To selections.