CalculatorShelf
Browse calculators
Browse by shelf

Choose a focused collection, or open the complete directory.

All calculators
StoragePlan capacity, performance, and reliability decisions for storage and PC hardware.Home ProjectsEstimate materials and quantities for practical home projects with visible assumptions.Pool & WaterEstimate pool volume from measured dimensions; use the guides to understand product and safety boundaries.ShippingEstimate shipping quantities, costs, and loading geometry before requesting a quote.LifestyleHandle everyday sizing, photography, wrapping, and seasonal planning questions.SportsExplore pace, motion, and sizing calculations with explicit assumptions and limits.BusinessPlan margin and language-service decisions from entered prices, costs, and volumes.Math & EducationCalculate arithmetic, scientific expressions, units, dates, algebra, physics, and education formulas with visible methods.FinanceCompare currency, bills, discounts, and fixed-rate loan scenarios with visible rates, rounding, and assumptions.
All calculatorsMethodology

Unit Converter

Convert length, area, volume, mass, temperature, speed, pressure, and decimal or binary data units with compatible-unit controls.

Interactive calculator · Method UNIT_CONVERSION-1.1 · Last reviewed: 2026-10-15

Enter your scenario

Results update as valid inputs change. Correct any highlighted field before relying on the answer.

Your inputs

Try an example
The category limits both unit lists to compatible dimensions.
Enter the quantity in the selected source unit.
Choose the unit attached to the entered amount.
Choose a compatible destination unit.
DirectionSwitch source and destination without retyping the amount.

Default worked example. Edit the inputs to calculate your scenario.

Default worked example

Converted amount 3.6576 m
Source amount 12 ft
Conversion category Length
Unit relationship 1 ft = 0.3048 m

12 feet equals 3.6576 meters.

How to use the calculator

Choose a measurement category, source unit and destination unit, then enter the amount. Use Swap units to reverse the conversion direction. Results update locally as you edit.

What the result means

The primary answer is the converted quantity. Small nonzero answers use scientific notation: 1.00e-11 means 0.00000000001. Calculations retain the underlying value; display rounding does not change it.

Formula and units

For length, area, volume, mass, speed, pressure and data, multiply by the source base-unit factor and divide by the destination factor. Temperature points require offsets: °F = °C × 9/5 + 32 and K = °C + 273.15. The result shows the formula for your selected pair.

Worked examples

12 feet to meters: Amount: 12 selected source unit; Measurement category: length; Convert from: ft; Convert to: m.
Example result: Converted amount: 3.6576 m; Source amount: 12 ft; Conversion category: Length; Unit relationship: 1 ft = 0.3048 m.

32 °F to Celsius: Amount: 32 selected source unit; Measurement category: temperature; Convert from: f; Convert to: c.
Example result: Converted amount: 0 °C; Source amount: 32 °F; Conversion category: Temperature; Unit relationship: °C = (°F − 32) × 5/9.

Limitations and common mistakes

Temperature means a point on a scale, not a temperature difference. This converter supports ordinary temperatures at or above absolute zero: −273.15 °C, −459.67 °F or 0 K. Volume uses US customary units; decimal data units and binary data units are distinct.

Do not use a temperature-point conversion for a temperature difference. A 10 °C rise is an 18 °F rise, whereas 10 °C as a temperature is 50 °F. Check US gallons versus other gallon definitions.

Sources and assumptions

Conversion factors are declared dimensional identities, with SI prefix meaning supported by NIST.

Method UNIT_CONVERSION-1.1; last formula review 2026-10-15. Sources and their supported claims. Calculation methodology.

NIST: SI Units – Temperature. Exact scale relationships and the absolute-zero boundary.