Unit Conversion Basics
What is unit conversion?
Unit conversion is the process of expressing the same quantity in a different unit of measurement, for example converting 5 kilometers into 3.107 miles. The physical amount does not change; only the unit used to describe it does. Every conversion relies on a fixed conversion factor, such as 1 inch = 2.54 cm. Try it instantly with our free online unit converter.
Why is unit conversion important?
Mixing up units causes real damage. In 1999 NASA lost the 125 million dollar Mars Climate Orbiter because one team used imperial units and another used metric. In daily life, unit conversion keeps medication doses safe, recipes accurate, engineering plans consistent and international trade possible, since most of the world uses metric while the US uses imperial units.
How do I do unit conversion?
Follow three steps: 1) find the conversion factor between the two units (for example 1 mile = 1.609344 km), 2) multiply when going from a larger unit to a smaller one, and 3) divide when going from a smaller unit to a larger one. Example: 3 km to meters is 3 × 1,000 = 3,000 m. Or skip the math and use our unit conversion calculator.
What is unit conversion in chemistry?
In chemistry, unit conversion is done with dimensional analysis, also called the factor-label method. You multiply a measurement by conversion factors written as fractions so that unwanted units cancel out. For example, converting 10 g of water to moles: 10 g × (1 mol / 18.02 g) = 0.555 mol. It is the foundation of stoichiometry calculations.
How do I calculate conversion cost per unit?
This one is an accounting term, not a measurement one. Conversion cost per unit = (direct labor + manufacturing overhead) ÷ units produced. Example: with $50,000 labor, $30,000 overhead and 20,000 units produced, the conversion cost per unit is $4.
Quick Conversion Answers
1 nm equals how many mm?
1 nanometer (nm) equals 0.000001 mm (1 × 10⁻⁶ millimeters). Put the other way around, 1 millimeter contains 1,000,000 nanometers. Convert more with the length converter.
1 mg equals how many ng?
1 milligram (mg) equals 1,000,000 nanograms (ng). The chain is: 1 mg = 1,000 µg (micrograms), and 1 µg = 1,000 ng. Convert more with the weight converter.
Metric Unit Conversion Chart
This metric unit conversion table shows how the most common prefixes relate to the base unit. It works the same for meters, grams and liters.
| Prefix | Symbol | Multiplier | Example |
|---|---|---|---|
| kilo | k | × 1,000 | 1 km = 1,000 m |
| (base unit) | — | × 1 | 1 m, 1 g, 1 L |
| centi | c | ÷ 100 | 1 cm = 0.01 m |
| milli | m | ÷ 1,000 | 1 mm = 0.001 m |
| micro | µ | ÷ 1,000,000 | 1 µg = 0.000001 g |
| nano | n | ÷ 1,000,000,000 | 1 nm = 10⁻⁹ m |
How to Build Your Own Unit Converter
How do I use the unit converter on a TI-84 Plus?
The TI-84 Plus has no converter built into the base OS, but Texas Instruments' free SciTools app adds one. Press the APPS key, select SciTools, press any key at the splash screen, then choose UNIT CONVERTER. Pick a category (length, mass, temperature, etc.), enter your value, select its current unit, then select the target unit to see the converted result.
How do I make a unit converter in Python?
Store conversion factors relative to a base unit in a dictionary, then divide the factors. This tiny script converts any length unit to any other:
factors = {"km": 1000, "m": 1, "cm": 0.01, "mm": 0.001, "mi": 1609.344, "ft": 0.3048, "in": 0.0254}
def convert(value, from_unit, to_unit):
return value * factors[from_unit] / factors[to_unit]
print(convert(5, "km", "mi")) # 3.106855...Add more dictionaries for weight, volume or temperature (temperature needs formulas, not factors).
How do I make a unit converter in Excel?
Excel has a built-in CONVERT function. With a number in cell A1, use =CONVERT(A1, "kg", "lbm") for kilograms to pounds or =CONVERT(A1, "mi", "km") for miles to kilometers. To create a full converter, put the unit codes in two dropdown lists (Data → Data Validation) and reference them: =CONVERT(A1, B1, C1).
How do I create a unit converter in Android Studio?
Build a layout with an EditText for the input value, two Spinners for the "from" and "to" units, and a TextView for the result. In Kotlin or Java, keep a map of conversion factors and compute result = value * factor(from) / factor(to) inside a TextWatcher or the Spinners' onItemSelected listener so the result updates live.
How do I make a unit converter in Visual Basic?
Add a TextBox for the value, two ComboBoxes for the units and a Label for the result. In the Convert button's Click event, look up each selected unit's factor and calculate result = value * fromFactor / toFactor, then display it with Label1.Text = result.ToString().
Ready to convert? Try the length, weight, temperature, volume, area, speed or data converter now.