Charts & references · 3 min read

Metric to Imperial Conversion Cheat Sheet (Exact Factors)

Published October 3, 2026Written and reviewed by Mateuss M.

In short: Most everyday conversions use a handful of exact factors: 1 inch = 2.54 cm, 1 mile = 1.609344 km and 1 pound = 0.45359237 kg.

Length

From	To	Factor
in	cm	1 in = 2.54 cm
ft	cm	1 ft = 30.48 cm
yd	m	1 yd = 0.9144 m
mi	km	1 mi = 1.609344 km
cm	in	1 cm = 0.3937007874 in
m	ft	1 m = 3.280839895 ft
km	mi	1 km = 0.6213711922 mi

Mass

From	To	Factor
oz	g	1 oz = 28.349523125 g
lb	kg	1 lb = 0.45359237 kg
kg	lb	1 kg = 2.2046226218 lb
g	oz	1 g = 0.0352739619 oz
t	kg	1 t = 1000 kg

Volume (US units)

From	To	Factor
floz	mL	1 floz = 29.5735295625 mL
cup	mL	1 cup = 236.5882365 mL
qt	L	1 qt = 0.946352946 L
gal	L	1 gal = 3.785411784 L
L	gal	1 L = 0.2641720524 gal

These are US customary volumes. The imperial (UK) gallon is about 20% larger.

Worked examples

Multiply by the factor, or divide by it to go back. The unit converter shows the multiplication.

A marathon (26.2 miles) in kilometres

Answer26.2 mi = 42.1648128 km

1 mi = 1.609344 km

Step-by-step working 2 steps

1
Find the conversion factor
```
1 mi = 1.609344 km
```
Both units are converted through a common base (metre).
2
Multiply
```
26.2 × 1.609344 = 42.1648128
```

180 pounds in kilograms

Answer180 lb = 81.6466266 kg

1 lb = 0.45359237 kg

Step-by-step working 2 steps

1
Find the conversion factor
```
1 lb = 0.45359237 kg
```
Both units are converted through a common base (kilogram).
2
Multiply
```
180 × 0.45359237 = 81.6466266
```

Frequently asked questions

How many centimetres are in an inch?

Exactly 2.54.

Are these factors exact?

The inch, pound and US volume units are defined exactly in terms of metric units, so these factors are exact (not rounded).

Written and reviewed by Mateuss M.

Mateuss M. writes and reviews mathematical content for CalcSolver, focusing on online calculators, formulas, equations, and practical math tools. He reviews calculator functionality, calculation methods, formulas, examples, and explanations to help ensure that each tool is clear, useful, and easy to understand.

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Charts & references

Metric to Imperial Conversion Cheat Sheet (Exact Factors)

Length

Mass

Volume (US units)

Worked examples

Frequently asked questions

Written and reviewed by Mateuss M.

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