Interactive length conversion and measurement studio

Length Converter and Measurement Calculator

Convert metric, imperial, nautical and astronomical length units, work with feet and fractional inches, convert human height, and calculate drawing scales with transparent formulas.

12 length units · fractions · height · drawing scale

Convert any length or distance

Enter one value to see the same length in every supported unit. The calculation keeps full precision internally and rounds only the displayed values.

Length value

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Converted measurement

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The same length in every unit

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Live conversion ruler

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Both rows represent the same physical length. Their labels show why the numeric values change when the unit changes.

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This length is about—

Real-world comparisons are approximate and individual objects vary.

Conversion formula and steps

Metric length units

Metric units scale by powers of ten. One metre equals 100 centimetres, 1,000 millimetres or one billion nanometres. One kilometre equals 1,000 metres.

Inches, feet, yards and miles

One foot contains 12 inches, one yard contains 3 feet, and one international mile contains exactly 5,280 feet. A US survey foot can differ in specialist legacy data, so use the stated standard for surveying work.

Working with fractional inches

Construction, woodworking and product dimensions often use fractions of an inch. The fraction mode accepts mixed values and can round the converted remainder to halves, quarters, eighths, sixteenths, thirty-seconds or sixty-fourths.

Understanding drawing scales

At 1:50, one unit on the drawing represents 50 of the same units in reality. Divide a real measurement by 50 to obtain its drawing size; multiply a drawing measurement by 50 to obtain the real size.

Precision and rounding

The calculator retains full floating-point precision during calculations. Choose more displayed decimal places for technical work and fewer for everyday measurements. Do not imply more accuracy than the original measurement provides.

Supported length units

Convert nanometres, micrometres, millimetres, centimetres, metres, kilometres, inches, feet, yards, international miles, nautical miles and light-years.

Related length and measurement tools

Continue with focused centimetre, inch, foot, metre, kilometre, mile, area and volume conversions.

Length Converter FAQ

How many centimetres are in one inch?

One international inch is exactly 2.54 centimetres. Multiply inches by 2.54 to obtain centimetres.

How many feet are in one metre?

One metre is approximately 3.280839895 feet. Divide metres by 0.3048 to obtain feet.

How do I convert feet and inches to centimetres?

Multiply the feet by 12, add the inches, then multiply the total inches by 2.54.

Can I enter fractional inches?

Yes. Enter a simple fraction such as 3/8 or a mixed fraction such as 11 1/2. The calculator also accepts decimals.

How is a 1:50 drawing scale calculated?

For real size to drawing size, divide the real measurement by 50. For drawing size to real size, multiply by 50.

What is the difference between a mile and a nautical mile?

An international mile is exactly 1,609.344 metres. A nautical mile is exactly 1,852 metres and is used in marine and air navigation.

How precise are the converted results?

The fixed conversion factors are accurate, but the meaningful precision of the result still depends on the accuracy of the value you entered.

Can I use a comma as the decimal separator?

Yes. The calculator accepts either a comma or a period as the decimal separator, as well as Arabic and Persian numerals.