Converters
Convert units, nutrition macros, material density, and wire gauge sizes. Standard unit factors follow BIPM and NIST definitions, with source-backed density values and NEC-based electrical assumptions where relevant.
Featured Converter Cohorts
Start with the three specialist converters below, or jump straight to a common nutrition, material-density, or wire-gauge conversion.
12 Active Converters
6 Categories
BIPM / NIST Verified
Weight
3Temperature
2Volume
2Speed
1Area
1Most Searched Converters
Frequently Asked Questions
How do unit converters work?
A unit converter multiplies your value by a fixed factor defined in international standards (BIPM, NIST). For example, one foot is defined as exactly 0.3048 meters, and every length conversion follows from that definition. The same factor applies at any scale.Are your conversions accurate?
Conversion factors come from official standards: BIPM (the International Bureau of Weights and Measures) for SI units, NIST for US customary units, and other national metrology institutes. Every factor is checked against published reference values before it is used.Can I convert between any units?
You can convert between any units within the same dimension (e.g., any length unit to any other length unit). However, you cannot directly convert across dimensions (e.g., length to weight) as they measure different physical quantities.
How these converters work
Conversions run from a unit registry: each unit carries its dimension, its ratio to that dimension's base unit, and any offset. Every pair page shows its own factor and reverse factor rather than a rounded approximation.
Exact ratios are used where one exists — an inch is defined as 25.4 mm — so only the displayed value is rounded.
Every page in this section carries:
- the conversion factor and its reverse, both stated to full precision
- a worked breakdown of the arithmetic for the value you entered
- a reference table of common values around your input
- definitions for both units, including which system each belongs to
- the rounding applied to the displayed result, stated on the page
Picking the right converter
Units sharing a name need not share a size: US and imperial fluid ounces differ by about 4%, their gallons by about 20%, and a US ton, long ton and tonne are three quantities. Each has its own page.
For a rate — miles per gallon, kilograms per cubic metre — use the compound-unit tool rather than converting numerator and denominator separately.
Where these tools stop
- Where a source label is ambiguous — "ton", "ounce", "gallon" — the conversion cannot resolve that for you.
- Temperature carries an offset as well as a ratio, so a difference and a reading convert differently.
- Displayed precision is not accuracy: a six-decimal result is only that precise if the input was.
The market in the URL controls the numbers: currency, measurement convention, and any regional rule that changes the calculation. The interface language is a separate browser setting that never changes a result — it translates the labels while the computation, its units and its sources stay as they are.
Checking our work
Where a page states a standard, constant or regulatory limit, it names the source so the figure can be traced back. The methodology page describes how tools are generated and validated, rounding policy documents how displayed values are rounded, and sources and standards lists the references behind the platform. If a figure looks wrong, the corrections policy explains how to report it and what happens next.