Equivalent lengths and displayed precision
The converted result represents the same distance in the target unit. The table lists that distance in every supported unit. Values use up to twelve significant digits, so small results can appear in scientific notation rather than being rounded to zero.
After matching the units of two perpendicular dimensions, use the Pythagorean Theorem Calculator to find their diagonal.
The formula
A common metre basis connects every pair of supported length units. For example, an international inch is exactly 0.0254 metres and an international foot is exactly 0.3048 metres. The original input is converted directly; table rows are not chained together. Feet/inches entry combines feet + inches/12 before using the same international-foot factor.
One international mile in kilometres
Choose International miles as From, enter 1, and select Kilometres as To. The result is 1.609344 km. The same distance is 1,609.344 metres or 5,280 international feet.
How to use this calculator
- Choose One decimal value or Feet and inches, then enter the active measurement fields.
- Select the target length unit and read the live result and equivalent table.
- Use Reverse this conversion to reuse the same distance in the opposite direction; Reset restores the example.
Enter decimal or combined feet and inches
Choose Feet and inches for a two-part measurement such as 5 feet 6 inches. It equals 5.5 decimal feet or 66 inches; it does not mean 5.6 feet. Decimal mode remains available for a measurement in any listed unit.
For a negative coordinate or signed displacement, use the magnitude here and retain the direction separately. This tool is intended for nonnegative lengths and distances.
Check which definition your document uses
The mile option is the international statute mile. A nautical mile is a separate unit, useful for marine or aviation distances, and is not interchangeable with a land mile.
Older surveying records may use the former U.S. survey foot. That unit is not offered here. Confirm the measurement definition before converting a historical survey or combining dimensions from different documents.
Keep the measurement when reversing
Five feet six inches converts to 167.64 cm. Reverse this conversion puts 167.64 into the value field with centimetres as From and feet as To, returning 5.5 ft. Mixed entries remain available when you switch back.
Reverse uses the numerical result before its twelve-significant-digit display rounding. If the target amount exceeds the input range, the current entries stay in place and a message asks you to choose another unit.
Assumptions & limitations
What this calculation assumes
- Inputs are nonnegative distances no greater than 1 trillion source units.
- Feet, inches, yards, and miles use international definitions.
What to keep in mind
- Feet/inches entry uses separate numeric fields; shorthand such as 5′6″ or fractions such as 1/2 are not parsed.
- This is a length conversion, so it does not directly convert square or cubic units.
Common questions
How do I enter 5 feet 6 inches?
Choose Feet and inches, enter 5 whole feet and 6 additional inches. You can also use 5.5 feet or 66 inches in decimal mode.
Can I convert square feet with this tool?
No. An area conversion squares the length factor. Use an area calculation with the appropriate squared units.
Why does a small result contain e−6?
Scientific notation keeps small nonzero distances readable. For example, 1e−6 is one millionth of the stated unit.
Sources & further reading
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