Metric to Imperial Converter

Supported conversions

The first row takes a length in nanometers, micrometers, millimeters, centimeters, decimeters, meters or kilometers. The second row shows it as inches, feet, yards, statute miles, nautical miles or leagues. All 42 pairings work, and the answer refreshes whenever you change a number or a unit.

Metric versus imperial lengths

Metric lengths build on the meter with prefixes that multiply or divide by powers of ten. A kilometer is 1,000 meters, a centimeter is a hundredth of one and a millimeter a thousandth. Almost every country uses this system for daily life, and science uses it everywhere.

Imperial lengths are older and irregular: 12 inches make a foot, 3 feet a yard, 1,760 yards a mile. The system is still the everyday standard in the United States, and it survives in British road signs, heights and some trades. Where the two meet, everything rests on one agreement from 1959, which defined the inch as exactly 25.4 millimeters.

That is why metric to imperial conversion is a division: to find out how many inches fit into a number of centimeters, divide by 2.54; for feet from meters, divide by 0.3048.

How to convert metric to imperial

1. Enter the metric length and choose its unit in the top row.
2. Select the imperial unit in the bottom row.
3. Read the converted number, then change either choice to compare other units.

imperial length = metric length × (meters per metric unit) ÷ (meters per imperial unit)For centimeters to inches this reduces to dividing by 2.54.

Results above 999 get thousands separators. Numbers are rounded to nine decimals and trailing zeros are dropped, so 2.54 cm shows as exactly 1 inch.

Quick reference tables

Rules of thumb

• 1 cm is about 0.4 in, so 10 cm is roughly 4 in.
• 1 m is about 3 ft 3⅜ in, or 1.09 yd.
• 1 km is about 0.62 mi. Multiply kilometers by 0.6 and add a little: 100 km/h is roughly 62 mph (exactly 62.1371).
• A 5K race is 3.1 miles and a 10K is 6.2 miles.

The estimates are within about 2 percent of the true value, good enough for planning but not for precision work.

Common mistakes

• Multiplying instead of dividing. Going from centimeters to inches gives a smaller number, so dividing by 2.54 is the right direction.
• Writing decimal feet as feet and inches. A result of 5.5 ft is 5 ft 6 in (0.5 × 12), not 5 ft 5 in.
• Applying a length factor to area or volume. A square meter is 10.7639 ft², not 3.2808 ft².
• Using miles when the source meant nautical miles, which are about 15% longer.

Notes on precision

Because answers are cut at nine decimals, extremely small inputs such as a few nanometers show as 0 or in exponent form. For a quick estimate by hand, 1 m is about 3.28 ft, 1 km is about 0.62 mi and 1 cm is about 0.39 in.

These are exact mathematical conversions. Product sizes, clothing and tire dimensions are often rounded by manufacturers, so their metric and imperial labels can differ slightly.

For single pairs there are focused pages: kilometers to miles, meters to feet and centimeters to inches. When you meet numbers with many zeros, the scientific notation calculator can rewrite them compactly.