Imperial to Metric Conversion: Guide for International Travelers and Professionals

Imperial to Metric: The Essential Guide

For Americans traveling abroad, scientists working with international colleagues, or anyone dealing with metric measurements, knowing how to convert from imperial to metric is essential.

Quick Reference Chart

Imperial	Metric	Conversion
1 mile	1.609 km	mi × 1.609
1 foot	0.305 m	ft × 0.305
1 inch	2.54 cm	in × 2.54
1 pound	0.454 kg	lb × 0.454
1 ounce	28.35 g	oz × 28.35
1 gallon	3.785 L	gal × 3.785
32°F	0°C	(°F - 32) × 5/9

Length Conversions

Miles to Kilometers

Formula: kilometers = miles × 1.60934

Quick Mental Math: Add 60% to miles

• 10 miles → 10 + 6 = 16 km

Feet to Meters

Formula: meters = feet × 0.3048

Quick Mental Math: Divide feet by 3.3

• 10 feet ≈ 3 meters

Inches to Centimeters

Formula: centimeters = inches × 2.54

Quick Mental Math: Multiply inches by 2.5

• 4 inches ≈ 10 cm

Height Conversion Table

Imperial	Metric
5'0"	152 cm
5'6"	168 cm
5'10"	178 cm
6'0"	183 cm
6'2"	188 cm

Weight Conversions

Pounds to Kilograms

Formula: kilograms = pounds × 0.453592

Quick Mental Math: Divide pounds by 2.2

• 110 lb ÷ 2.2 = 50 kg

Body Weight Conversions

Pounds	Kilograms
100 lb	45 kg
140 lb	64 kg
160 lb	73 kg
180 lb	82 kg
200 lb	91 kg

Temperature Conversion

Fahrenheit to Celsius

Formula: °C = (°F - 32) × 5/9

Quick Mental Math: Subtract 30, then divide by 2

• 70°F → (70 - 30) / 2 = 20°C (actual: 21°C)

Common Temperature Conversions

Fahrenheit	Celsius	Description
32°F	0°C	Freezing
50°F	10°C	Cool
68°F	20°C	Room temp
86°F	30°C	Warm
98.6°F	37°C	Body temp

Oven Temperature Conversions

Fahrenheit	Celsius	Gas Mark
300°F	150°C	2
350°F	175°C	4
400°F	200°C	6
450°F	230°C	8

Volume Conversions

Gallons to Liters

Formula: liters = US gallons × 3.78541

Quick Mental Math: Multiply gallons by 4

• 5 gallons ≈ 20 L

Fluid Ounces to Milliliters

Formula: milliliters = fluid oz × 29.5735

Speed Conversions

MPH to KM/H

Formula: km/h = mph × 1.60934

US Speed Limits in Metric

US Limit	Metric Equivalent
25 mph	40 km/h
55 mph	89 km/h
65 mph	105 km/h
75 mph	121 km/h

Conclusion

Imperial to metric conversion is straightforward once you know the formulas. With practice, common conversions will become second nature.

Use our free Unit Converter tool for quick and accurate conversions anytime you need them.