About

Accuracy in unit conversion is the bedrock of engineering, science, and international trade. A single decimal error in converting meters to feet or kilograms to pounds can lead to catastrophic structural failures or significant financial loss. This tool is engineered to eliminate ambiguity by providing exact conversion factors and handling the nuances between systems, such as the distinction between US Liquid Gallons and Imperial Gallons.

While simple estimators suffice for rough approximations, professional contexts demand precision. This converter implements IEEE 754 floating-point arithmetic safeguards, distinct algorithms for non-linear scales like temperature, and supports fractional output for carpentry and machining applications. It handles edge cases like absolute zero in thermodynamics and prevents invalid negative inputs for scalar physical quantities like mass and length.

Formulas

The core logic relies on a Normalization Pattern. All input values are first converted to a base SI unit (e.g., meters, kilograms, kelvin) before being projected to the target unit. This ensures O(n) complexity for adding new units rather than O(n²).

{

Val_base = f_in(Val_input)Val_output = f_out(Val_base)

For Temperature (Non-linear):

{

T_°C = (T_°F − 32) × 59T_K = T_°C + 273.15

Reference Data

Category	Unit A	Unit B	Exact Factor / Formula	Notes
Length	1 Inch (in)	25.4 Millimeters (mm)	L_mm = L_in × 25.4	International Yard and Pound Agreement (1959)
Length	1 Meter (m)	3.28084 Feet (ft)	L_ft ≈ L_m × 3.28084	Approximation for general use
Mass	1 Kilogram (kg)	2.20462 Pounds (lb)	M_lb ≈ M_kg × 2.20462	Standard gravity assumed
Volume	1 US Gallon (gal)	3.78541 Liters (L)	V_L ≈ V_gal × 3.78541	Different from UK Imperial Gallon (4.546 L)
Temp	Fahrenheit (°F)	Celsius (°C)	(T_°F − 32) × 59	Non-linear offset conversion
Speed	1 Knot (kn)	1.852 km/h	S_km/h = S_kn × 1.852	Based on International Nautical Mile

Frequently Asked Questions

This is a common issue caused by the difference between the US Liquid Gallon (approx. 3.785 L) and the Imperial (UK) Gallon (approx. 4.546 L). Our tool explicitly separates these units to prevent mixing standards.

When converting to inches, the tool automatically detects if the decimal value is close to a standard fraction (e.g., 1/16, 1/32) and displays the fractional equivalent alongside the decimal for ease of use in carpentry and fabrication.

Yes. The "Stone" is a British Imperial unit of mass equal to exactly 14 pounds. We use the precise factor: 1 st = 6.35029318 kg.

For Temperature, yes. For scalar physical quantities like Length, Mass, and Volume, the tool enforces non-negative constraints to reflect physical reality (e.g., you cannot have -5 meters).