Universal unit converter
target_value = source_value × factor
Choose a quantity type, a source unit and a target unit: the result updates live, with the conversion factor or formula used shown below it. Every unit here shares the same conversion engine as the rest of the site.
1 Nanometer (nm) = 0.001 Micrometer (µm)
Raw value: 0.001
Scientific dossier
What the tool computes, what it assumes, where it stops being valid, and where its data comes from.
Method & formulastarget_value = source_value × factor
target_value = source_value × factor
target_value = f(source_value)
Most conversions (length, mass, volume…) are a simple multiplicative factor: doubling the value doubles the result. Temperature is the exception: an affine conversion (°C, °F, K) has no single factor, so the full formula is used instead. That is why the converter shows one or the other depending on the case, never a made-up factor.
- Base unit
- · the internal reference unit for each category (meter for length, kelvin for temperature...): every conversion passes through it, which guarantees consistency between any two units of the same category.
- Conversion factor
- · the number to multiply a value by to go from one unit to another, when the relationship is proportional.
- Affine conversion
- · a relationship that includes an offset in addition to a factor (e.g. °C to °F): it cannot be reduced to a simple factor, unlike most other categories.
- Raw value
- · the result in machine format (decimal point), distinct from the localized display, ready to be pasted into a calculation or a spreadsheet.
Validity domainTemperature rejects any value below absolute zero (0 K), regardless of the input unit.
Temperature rejects any value below absolute zero (0 K), regardless of the input unit. Other categories accept zero and negative values when they make physical sense (a coordinate, a difference): the converter doesn't know the context of use, so it doesn't impose a sign constraint beyond that one case.
How it worksPick a quantity type (length, mass, temperature.
Pick a quantity type (length, mass, temperature...), then a source unit and a target unit: the result appears immediately, no button to click. The "Swap" button exchanges the two units without clearing the value you entered.
Precision and raw valueThe displayed result is rounded to 6 significant figures to stay readable.
The displayed result is rounded to 6 significant figures to stay readable. A "raw value" is shown separately (decimal point, machine notation): that is the one copied to the clipboard and exported to CSV, so it stays directly reusable in a calculation or a spreadsheet regardless of display language.