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Metric Converter

Convert metric length units across prefixes, from nanometers up to megameters, using meters as the reference.

Formula shown0 inputs definedUpdated Dec 2025By CalcuTotal TeamFree, no sign-up

Quick Summary

Use this when you need:

Convert drawings and specs between mm, cm, m, and km
Translate microscope-scale values (nm, μm) into mm for reporting
Normalize values into meters before using SI formulas

You’ll get:Length

How this is calculated

Formula:

value_target = value_source × 10^(prefix_source - prefix_target)

In plain language:

Metric prefixes represent powers of ten. This converter routes everything through meters so each step stays a simple multiply or divide by 10, 100, 1000, and so on.

The formula is always visible so you can verify the math and explain your numbers to anyone who asks.

What these terms mean

Length

Length used in the calculation.

When to use this calculator

Convert drawings and specs between mm, cm, m, and km
Translate microscope-scale values (nm, μm) into mm for reporting
Normalize values into meters before using SI formulas

Last updated: December 26, 2025

Metric converter explained

Metric units are built on powers of ten. That is helpful until you have to jump between mm, cm, m, and km in the same spec sheet. This metric converter keeps common metric prefixes in one view and converts through meters to stay consistent.

How the conversion works

Every metric length unit is a scaled version of the meter:

1\\,\\text{km} = 1000\\,\\text{m}

1\\,\\text{cm} = 0.01\\,\\text{m}

So conversion is multiplication or division by a power of ten.

Units and conversions

Unit	Symbol	Relation to meters
Nanometer	nm	$10^{-9}\\,\\text{m}$
Micrometer	μm	$10^{-6}\\,\\text{m}$
Millimeter	mm	$10^{-3}\\,\\text{m}$
Centimeter	cm	$10^{-2}\\,\\text{m}$
Meter	m	base unit
Kilometer	km	$10^{3}\\,\\text{m}$

Worked examples

Converting 1200 mm to meters
$1200\\,\\text{mm} = 1200 \\times 10^{-3}\\,\\text{m} = 1.2\\,\\text{m}$
Result: 1.2 m.
Converting 0.75 km to centimeters
$0.75\\,\\text{km} = 0.75 \\times 1000\\,\\text{m} = 750\\,\\text{m}$ $750\\,\\text{m} = 750 \\times 100\\,\\text{cm} = 75000\\,\\text{cm}$
Result: 75000 cm.

Tips and pitfalls

Write units next to every number in your notes; metric prefixes are easy to drop when you copy values.
For machining and fabrication, keep mm as your working unit to avoid rounding drift from repeated conversions.
For small-scale work, remember the chain: $1\\,\\text{mm} = 1000\\,\\mu\\text{m} = 1{,}000{,}000\\,\\text{nm}$ .

References and further reading

Frequently Asked Questions

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Calculator info

Version:: v1.0.0
Last reviewed:: Dec 26, 2025
Sensitivity:: low
References:: 2

Last updated: December 26, 2025

Metric converter explained

How the conversion works

Every metric length unit is a scaled version of the meter:

1\\,\\text{km} = 1000\\,\\text{m}

1\\,\\text{cm} = 0.01\\,\\text{m}

So conversion is multiplication or division by a power of ten.

Units and conversions

Unit	Symbol	Relation to meters
Nanometer	nm	$10^{-9}\\,\\text{m}$
Micrometer	μm	$10^{-6}\\,\\text{m}$
Millimeter	mm	$10^{-3}\\,\\text{m}$
Centimeter	cm	$10^{-2}\\,\\text{m}$
Meter	m	base unit
Kilometer	km	$10^{3}\\,\\text{m}$

Worked examples

Converting 1200 mm to meters
$1200\\,\\text{mm} = 1200 \\times 10^{-3}\\,\\text{m} = 1.2\\,\\text{m}$
Result: 1.2 m.
Converting 0.75 km to centimeters
$0.75\\,\\text{km} = 0.75 \\times 1000\\,\\text{m} = 750\\,\\text{m}$ $750\\,\\text{m} = 750 \\times 100\\,\\text{cm} = 75000\\,\\text{cm}$
Result: 75000 cm.

Tips and pitfalls

Write units next to every number in your notes; metric prefixes are easy to drop when you copy values.
For machining and fabrication, keep mm as your working unit to avoid rounding drift from repeated conversions.
For small-scale work, remember the chain: $1\\,\\text{mm} = 1000\\,\\mu\\text{m} = 1{,}000{,}000\\,\\text{nm}$ .

Quick Summary

Calculator Tool

How this is calculated

What these terms mean

Length

When to use this calculator

Metric converter explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

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Was this calculator helpful?

Found an error?

Calculator info

Metric converter explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

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Angstrom to nm converter

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