Length
Convert between measurement systems
Convert scientific, metric, and imperial units in real time.
Convert units instantly with this free online Unit Converter. Easily switch between length, weight, temperature, area, volume, speed, time, energy, pressure, digital storage, and many other measurement units with precise real-time calculations.
Whether you are a student, engineer, designer, traveler, developer, scientist, or simply need quick everyday conversions, this tool helps you convert values accurately in seconds.
Popular Conversions
Our converter supports a wide range of commonly used conversions, including:
- Meters to feet
- Kilometers to miles
- Celsius to Fahrenheit
- Kilograms to pounds
- Liters to gallons
- Square meters to square feet
- Bytes to megabytes
- Watts to horsepower
- PSI to bar
- Seconds to hours
You can quickly enter a value, select the units, and get instant results without reloading the page.
International System of Units (SI)
International System of Units (SI)
The International System of Units (SI), or Metric System, is the most widely adopted measurement system globally. It’s used by scientists and many countries for consistency and ease of communication across international borders. The SI is based on a decimal system and includes seven base units:
- Meter (m) – for length
- Kilogram (kg) – for mass
- Second (s) – for time
- Ampere (A) – for electric current
- Kelvin (K) – for temperature
- Mole (mol) – for amount of substance
- Candela (cd) – for luminous intensity
These units can be modified by adding prefixes to represent different scales (e.g., milli-, centi-, kilo-, mega-), making them versatile for measuring everything from microscopic distances to astronomical ones.
The International System is a standard established and revised by BIPM (Bureau International des Poids et Mesures -International Bureau of Weights and Measures).
Imperial Units
Imperial System
The Imperial System is primarily used in the United States and a few other countries. It includes units such as:
- Inches, Feet, and Yards – for length
- Pounds and Ounces – for weight
- Gallons and Pints – for volume
Unlike the SI, the Imperial System does not follow a base-10 structure, which can make conversions challenging. However, it remains widely used in certain applications, particularly in construction and industry in the U.S.
Scales prefixes
Scales and Prefixes
Scales and prefixes allow measurements to be represented in manageable quantities, regardless of their magnitude. Here are some standard prefixes:
| Prefix | Symbol | Factor | 10^ | Scale |
|---|---|---|---|---|
| Yotta | Y | 1,000,000,000,000,000,000,000 | 1024 | Septillion |
| Zetta | Z | 1,000,000,000,000,000,000 | 1021 | Sextillion |
| Exa | E | 1,000,000,000,000,000 | 1018 | Quintillion |
| Peta | P | 1,000,000,000,000 | 1015 | Quadrillion |
| Tera | T | 1,000,000,000,000 | 1012 | Trillion |
| Giga | G | 1,000,000,000 | 109 | Billion |
| Mega | M | 1,000,000 | 106 | Million |
| Kilo | k | 1,000 | 103 | Thousand |
| Hecto | h | 100 | 102 | Hundred |
| Deca | da | 10 | 101 | Ten |
| Base Unit | – | 1 | 100 | One |
| Deci | d | 0.1 | 10-1 | Tenth |
| Centi | c | 0.01 | 10-2 | Hundredth |
| Milli | m | 0.001 | 10-3 | Thousandth |
| Micro | µ | 0.000001 | 10-6 | Millionth |
| Nano | n | 0.000000001 | 10-9 | Billionth |
| Pico | p | 0.000000000001 | 10-12 | Trillionth |
| Femto | f | 0.000000000000001 | 10-15 | Quadrillionth |
| Atto | a | 0.000000000000000001 | 10-18 | Quintillionth |
| Zepto | z | 0.000000000000000000001 | 10-21 | Sextillionth |
| Yocto | y | 0.000000000000000000000001 | 10-24 | Septillionth |
More
Why Use This Unit Converter?
Accurate Calculations
All conversions are calculated using standardized conversion formulas for reliable results.
Fast and Easy to Use
Simply type a value, choose your units, and the converter updates instantly.
Mobile Friendly
Use the converter on desktop, tablet, or smartphone with a responsive interface.
Free Online Tool
No downloads, subscriptions, or registration required.
Common Conversion Examples
How many feet are in a meter?
1 meter equals approximately 3.28084 feet.
How many pounds are in a kilogram?
1 kilogram equals approximately 2.20462 pounds.
How do you convert Celsius to Fahrenheit?
Use the formula:
F = (C × 9/5) + 32
How many liters are in a gallon?
1 US gallon equals approximately 3.78541 liters.
Frequently Asked Questions
What is a unit converter?
A unit converter is a tool that transforms one measurement unit into another while maintaining the same quantity value.
Are the conversions accurate?
Yes. The calculations use internationally recognized conversion standards.
Can I use this converter on mobile devices?
Yes. The tool is fully responsive and optimized for phones and tablets.
Is this unit converter free?
Yes. All conversions are completely free to use.
What measurement systems are supported?
The converter supports both Metric and Imperial systems, along with scientific and digital measurement units.
About Measurement Units
Measurement units are standardized quantities used to express physical values such as distance, weight, temperature, speed, and energy. Different countries and industries use different systems, including the Metric System and the Imperial System.
Having a reliable unit conversion tool helps avoid errors in engineering, science, cooking, construction, education, travel, and everyday calculations.
