What This Calculator Does
This unit converter handles seven categories of measurement: Length, Mass/Weight, Temperature, Area, Volume, Speed, and Digital Storage. Enter a value in one unit and instantly see the equivalent in another unit within the same category. The conversion formula is displayed alongside the result.
Inputs Explained
- Category: The type of measurement — Length, Mass, Temperature, Area, Volume, Speed, or Digital Storage.
- From Value: The numeric value you want to convert.
- From Unit: The unit of the input value (e.g., meters, kilograms, Celsius).
- To Unit: The target unit for conversion (e.g., feet, pounds, Fahrenheit).
- Scientific Notation: Toggle to display results in scientific notation for very large or very small numbers.
How It Works
For most categories, the converter uses a base-unit approach. Each unit has a conversion factor relative to a base unit (e.g., meters for length). The input value is first converted to the base unit, then from the base unit to the target unit. Temperature uses specific formulas since the conversion between Celsius, Fahrenheit, and Kelvin is not a simple ratio.
Key Formulas
General: Result = Value × (From Factor ÷ To Factor)
Temperature:
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
K = °C + 273.15
Temperature:
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
K = °C + 273.15
Unit Converter
Result
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Formula:
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Step-by-Step Example: Length Conversion
Input: 5 miles
Target Unit: kilometers
Step 1: 1 mile = 1609.344 meters (base unit).
Step 2: 5 miles = 5 × 1609.344 = 8046.72 meters.
Step 3: 1 kilometer = 1000 meters, so 8046.72 ÷ 1000 = 8.04672 km.
Result: 5 miles = 8.047 kilometers.
Step-by-Step Example: Temperature Conversion
Input: 98.6 °F
Target Unit: °C
Step 1: Apply formula: °C = (98.6 − 32) × 5/9
Step 2: °C = 66.6 × 5/9 = 37.0
Result: 98.6 °F = 37.0 °C (normal body temperature).
Use Cases
- Cooking: Convert recipe measurements between metric and imperial systems (grams to ounces, liters to cups).
- Travel: Convert miles to kilometers, Fahrenheit to Celsius, or gallons to liters when visiting countries using different systems.
- Science and engineering: Convert between SI and other unit systems for calculations, reports, or lab work.
- Computing: Convert between bytes, kilobytes, megabytes, gigabytes, and terabytes for storage planning.
- Fitness: Convert body weight between pounds and kilograms, or running distances between miles and kilometers.
Assumptions and Limitations
- Conversion factors are precise to at least 6 significant digits for physical units.
- Digital storage uses binary prefixes (1 KB = 1024 bytes), which is the convention used by operating systems and programming.
- Temperature conversion uses exact formulas, not approximations.
- The converter does not handle compound units (e.g., miles per gallon, kilowatt-hours) — only single units per category.
- Scientific notation can be toggled for results smaller than 0.001 or larger than 1,000,000.
Frequently Asked Questions
This converter supports seven categories: Length (meters, feet, miles, etc.), Mass/Weight (kilograms, pounds, ounces, etc.), Temperature (Celsius, Fahrenheit, Kelvin), Area (square meters, acres, hectares, etc.), Volume (liters, gallons, cubic meters, etc.), Speed (km/h, mph, m/s, etc.), and Digital Storage (bytes, KB, MB, GB, TB, etc.).
Most unit conversions are simple multiplications because the scales share a zero point. Temperature scales have different zero points — 0°C is 32°F and 273.15K. This means temperature requires both multiplication and addition/subtraction (affine transformation) rather than a single conversion factor.
This converter uses the binary convention where 1 KB equals 1024 bytes, 1 MB equals 1,048,576 bytes, and so on. This is the convention used by operating systems, programming languages, and memory manufacturers. The SI decimal convention (1 kB = 1000 bytes) is used by storage drive manufacturers and network standards.
Select the Area category, enter your value in square feet as the From unit, and select square meters as the To unit. The conversion factor is 1 square foot = 0.092903 square meters. For example, 1,000 sq ft ≈ 92.9 sq meters.
Mass measures the amount of matter in an object (measured in kilograms). Weight measures the gravitational force on that mass (measured in newtons). In everyday usage and in this converter, 'weight' and 'mass' are used interchangeably because we assume standard Earth gravity. A kilogram of mass weighs approximately 9.81 newtons on Earth.
Yes. Every category includes both metric and imperial units. For length, you can convert between meters and feet, kilometers and miles, centimeters and inches. For mass, between kilograms and pounds or ounces. For volume, between liters and gallons or fluid ounces. The converter handles all cross-system conversions.
Results are displayed with up to 6 significant figures by default. The underlying conversion factors are stored with high precision. For most everyday purposes, this is more than sufficient. If you need exact precision for scientific work, consider using the scientific notation toggle for results with very large or very small values.
Scientific notation expresses numbers as a coefficient between 1 and 10 multiplied by a power of 10. For example, 0.000001 becomes 1 × 10⁻⁶ and 1,500,000 becomes 1.5 × 10⁶. Toggle this option when converting between units with vastly different scales, such as bytes to terabytes or millimeters to kilometers.
Sources and References
- NIST Special Publication 811 – Guide for the Use of the International System of Units — Official U.S. reference for SI unit definitions and conversion factors.
- Bureau International des Poids et Mesures (BIPM) – The SI — International authority defining the metric system and SI base units.
- NIST Handbook 44 – Specifications for Weighing and Measuring Devices — U.S. standards for measurement conversions used in commerce.
- IEC 80000-13 – Quantities and Units for Information Technology — International standard defining binary prefixes for digital storage units.
- Schema.org FAQPage Specification — Structured data standard for the FAQ section markup.