Free Online Unit Converter

Instantly convert between different units of measurement including length, weight, volume, temperature, and area. accurate conversions for students, engineers, and everyday use.

Conversion Result

1 meter = 100 centimeters

Conversion History

Foundational Concepts: Understanding Unit Systems

Unit systems provide standardized ways to measure physical quantities. Understanding these systems is crucial for accurate conversions and scientific communication.

Convert values across length, weight, area, volume, speed, temperature and more. Supports both metric and imperial units with instant results. Access Tools, Master Formulas, and Understand Measurement Systems.

SI (Metric) vs. Imperial and US Customary Systems

The International System of Units (SI), commonly known as the metric system, is based on powers of ten and is used by most countries worldwide. In contrast, the Imperial system (used in the UK) and US Customary system use historical measurements not based on decimal factors.

Base Units vs. Derived Units

Base units are the fundamental measurements in a system (like meters for length or kilograms for mass). Derived units are combinations of base units (like meters per second for speed or newtons for force).

Mastering Conversion Methods and Formulas

Understanding the mathematical principles behind unit conversion ensures accuracy and helps identify potential errors in calculations.

Step-by-Step Dimensional Analysis

Dimensional analysis involves multiplying by conversion factors arranged as fractions so that unwanted units cancel out. For example, to convert 5 feet to meters: 5 ft × (0.3048 m/1 ft) = 1.524 m.

Precision, Rounding, and Significant Figures

The precision of your conversion depends on the significant figures in your original measurement and the precision of your conversion factors. Always consider the appropriate number of decimal places for your application.

Comprehensive Guide to Conversion Categories

Our converter supports a wide range of measurement types. Below are the most common categories with examples of conversions.

Length Conversions

Meters, feet, inches, miles, kilometers

Weight/Mass Conversions

Kilograms, pounds, ounces, grams, tons

Temperature Conversions

Celsius, Fahrenheit, Kelvin

Volume Conversions

Liters, gallons, milliliters, cubic meters

Area Conversions

Square meters, square feet, acres, hectares

Speed Conversions

Meters per second, miles per hour, kilometers per hour

Niche Conversions (Pressure, Energy, Digital/Crypto Units)

For specialized applications, we provide conversions for pressure (PSI to Bar), energy (Joules to BTUs), and even digital units relevant to blockchain technology.

Advanced Applications for Professionals and Students

Beyond basic conversions, our tools support advanced use cases for technical professionals and educational purposes.

Integrating Conversion APIs and Data (Developer Resources)

Developers can integrate our conversion algorithms via API for automated calculations in applications, websites, and backend systems.

Educational Practice and Unit Conversion Quizzes

Students can use our interactive quizzes and practice problems to master dimensional analysis and unit conversion techniques.

Frequently Asked Questions

What is the primary purpose of an online unit converter? +
An online unit converter allows users to instantly translate a measurement value from one system of units (like meters) to another (like feet) using precise conversion factors, satisfying a quick transactional need.
How do online converters handle specialized engineering or scientific units? +
Specialized converters (like those found on engineering or industry-specific websites) provide conversion functions for complex units, including pressure (e.g., PSI to Bar), energy (Joules to BTUs), and specific heat measurements.
What is the difference between SI units and Imperial units? +
The International System of Units (SI), or Metric system, is based on powers of ten and is used by most countries worldwide, while the Imperial system (or US Customary system) uses historical measurements not based on decimal factors.
How do conversion factors work in unit conversion? +
A conversion factor is a ratio, derived from the equivalence of two different units (e.g., 1 meter / 3.28 feet), which is multiplied by the original measurement to cancel out the initial unit and introduce the desired unit.
Which categories of conversion are most common on these tools? +
The most commonly featured categories across top-ranking tools include length, weight/mass, volume, area, temperature, and time.
Is the conversion process always precise, or should I worry about rounding? +
While conversion tools utilize precise mathematical constants, you should check the number of decimal places or significant figures reported, as rounding differences can become crucial in high-precision scientific or engineering applications.