Convert centimeters to kilometers

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Enter a value in centimeters and read the result in kilometers. It takes 100,000 centimeters to make a kilometer, so 250,000 cm is 2.5 km. Below there is a table of ready conversions with scientific notation, plus the ground distance behind a length measured on a map.

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What is a centimeter, and what is a kilometer?

A centimeter is the unit you can see on a ruler: one hundredth of a meter, divided further into ten millimeters. It is the scale for height, furniture and paper sizes, because the answer stays within two or three digits.

The kilometer describes the far end of the same scale. It holds 1,000 meters and it is the preferred unit for distances between places on land in most of the world; the United States, the United Kingdom and Liberia are the exceptions, where the statute mile is used[1]. Both units take their value from the meter and from an SI prefix: centi- is one hundredth and kilo- is one thousand[2].

That is where the distance between them comes from. Turning a centimeter into a kilometer means growing it one hundred thousand times, because five rungs of the metric ladder separate them. One centimeter written in kilometers therefore carries four zeros after the point before the first digit arrives, and the field above and the table below both hand you that number straight away.

A topographic map sheet with contour lines, heights in meters and grid lines
The sheet shows brown contour lines, spot heights in meters and black grid lines. The spacing between those lines converts to kilometers according to the scale of the sheet. Photo: Etienne Girardet, Unsplash.

How many kilometers are in a centimeter?

One centimeter is 0.00001 kilometers. Read the other way the arithmetic gives a round figure: 100,000 centimeters make exactly one kilometer.

Every conversion in this direction comes down to dividing the number of centimeters by one hundred thousand. One thousand centimeters is 0.01 kilometers. Ten thousand centimeters gives 0.1 kilometers. Five hundred thousand centimeters is 5 kilometers.

Short lengths start with a run of zeros, and that is when reading the answer off a ready table is quickest. One hundred centimeters, a meter, is 0.001 kilometers. Twenty-five thousand centimeters gives 0.25 kilometers, a quarter of a kilometer.

Scientific notation states the same values more briefly. A centimeter is 1 × 10⁻⁵ km, and a thousand centimeters is 1 × 10⁻² km. A negative exponent counts the places the decimal point moves to the left.

The converter above works in both directions and shows the result while you are still typing, so you can check any number of centimeters without counting zeros.

How do you convert centimeters to kilometers? Formula and example

The conversion rests on a fixed relationship: 100,000 centimeters make one kilometer. To turn centimeters into kilometers you divide their number by one hundred thousand.

The full formula: kilometers = centimeters ÷ 100,000. The other way round: centimeters = kilometers × 100,000.

Three examples of different sizes come out of that formula. Two hundred and fifty thousand centimeters divided by one hundred thousand gives 2.5 kilometers. Five thousand centimeters is 0.05 kilometers, that is fifty meters. One hundred centimeters, a meter, works out at 0.001 kilometers.

On paper the division is a single move of the decimal point, five places to the left. From 150,000 centimeters you get 1.5 kilometers, and from 4.5 centimeters you get 0.000045 kilometers. Fill the places in front of the digits with zeros.

In the other direction the operation is reversed: you multiply by one hundred thousand and the point travels five places to the right. That is what the kilometers to centimeters converter does. If going through meters suits you better, the centimeters to meters converter handles that step.

How many kilometers does a given number of centimeters make?

The table gathers lengths you would measure with a ruler, values in the hundreds of centimeters, and figures large enough to pass a kilometer. Every result is the number of centimeters divided by one hundred thousand.
CentimetersKilometersScientific notation
1 cm0.00001 km1 × 10⁻⁵ km
2 cm0.00002 km2 × 10⁻⁵ km
2.5 cm0.000025 km2.5 × 10⁻⁵ km
4.5 cm0.000045 km4.5 × 10⁻⁵ km
5 cm0.00005 km5 × 10⁻⁵ km
6 cm0.00006 km6 × 10⁻⁵ km
7 cm0.00007 km7 × 10⁻⁵ km
7.5 cm0.000075 km7.5 × 10⁻⁵ km
10 cm0.0001 km1 × 10⁻⁴ km
12 cm0.00012 km1.2 × 10⁻⁴ km
15 cm0.00015 km1.5 × 10⁻⁴ km
20 cm0.0002 km2 × 10⁻⁴ km
24 cm0.00024 km2.4 × 10⁻⁴ km
25 cm0.00025 km2.5 × 10⁻⁴ km
30 cm0.0003 km3 × 10⁻⁴ km
50 cm0.0005 km5 × 10⁻⁴ km
85 cm0.00085 km8.5 × 10⁻⁴ km
100 cm0.001 km1 × 10⁻³ km
500 cm0.005 km5 × 10⁻³ km
825 cm0.00825 km8.25 × 10⁻³ km
1,000 cm0.01 km1 × 10⁻² km
2,050 cm0.0205 km2.05 × 10⁻² km
2,500 cm0.025 km2.5 × 10⁻² km
3,200 cm0.032 km3.2 × 10⁻² km
4,900 cm0.049 km4.9 × 10⁻² km
5,000 cm0.05 km5 × 10⁻² km
7,500 cm0.075 km7.5 × 10⁻² km
10,000 cm0.1 km1 × 10⁻¹ km
50,000 cm0.5 km5 × 10⁻¹ km
91,000 cm0.91 km9.1 × 10⁻¹ km
100,000 cm1 km1 × 10⁰ km
500,000 cm5 km5 × 10⁰ km
1,000,000 cm10 km1 × 10¹ km
10,000,000 cm100 km1 × 10² km
The last column gives the same result as a power of ten, where a negative exponent moves the decimal point to the left. The conversion in the opposite direction is handled by the kilometers to centimeters converter.

How many kilometers on the ground does one centimeter on the map cover?

The number after the colon says how many times the ground has been shrunk. At 1:50,000 one centimeter of paper stands for 50,000 centimeters of ground, which is half a kilometer.
Map scaleDistance on the groundWhere you meet this scale
1:5,0000.05 kmCadastral and planning maps
1:10,0000.1 kmLarge-scale urban mapping
1:24,0000.24 kmUSGS US Topo quadrangles across the United States
1:25,0000.25 kmOS Explorer walking maps in Great Britain
1:50,0000.5 kmOS Landranger maps covering a whole region
1:100,0001 kmCounty and cycling maps
1:200,0002 kmState and county overview maps
1:500,0005 kmCountry-wide driving maps
1:1,000,00010 kmOverview maps and atlases
Ordnance Survey states the same relationship the other way round for its 1:25,000 Explorer sheets, where the grid lines are exactly 4 cm apart and every square is one kilometer across[3]. American quadrangles sit at 1:24,000, the scale the printed 7.5-minute series used from 1947 to 2006[4].

How many kilometers does a length measured on the map come to?

You multiply the length you measured by the number after the colon and divide by one hundred thousand. The results below cover three scales at once.
Length on the mapScale 1:25,000Scale 1:50,000Scale 1:100,000
2 cm on the map0.5 km1 km2 km
2.5 cm on the map0.625 km1.25 km2.5 km
3 cm on the map0.75 km1.5 km3 km
4 cm on the map1 km2 km4 km
5 cm on the map1.25 km2.5 km5 km
7.5 cm on the map1.875 km3.75 km7.5 km
10 cm on the map2.5 km5 km10 km
12 cm on the map3 km6 km12 km
15 cm on the map3.75 km7.5 km15 km
20 cm on the map5 km10 km20 km
Four centimeters is the side of a one-kilometer square on a 1:25,000 map. On a 1:50,000 map that same square measures 2 cm across.
The centimeter and millimeter scale of a caliper, close up
A caliper is divided the same way as the ordinary ruler you measure a map distance with: ten millimeters to every centimeter. The reading in centimeters is multiplied by the number after the colon and divided by one hundred thousand to give kilometers. Photo: Bozhin Karaivanov, Unsplash.

How many kilometers does each unit of the metric ladder hold?

Every unit on this ladder rests on the meter, and neighbouring rungs differ by a factor of ten. The last column states the same value as a power of ten.
UnitSymbolKilometersScientific notation
Millimetermm0.000001 km1 × 10⁻⁶ km
Centimetercm0.00001 km1 × 10⁻⁵ km
Decimeterdm0.0001 km1 × 10⁻⁴ km
Meterm0.001 km1 × 10⁻³ km
Dekameterdam0.01 km1 × 10⁻² km
Hectometerhm0.1 km1 × 10⁻¹ km
Kilometerkm1 km1 × 10⁰ km
The millimeter and the centimeter from the first two rows are converted into each other by the millimeters to centimeters converter. The dekameter and the hectometer stay in the table because without them the ladder would jump straight from the meter to the kilometer.

How do you convert centimeters to kilometers in a spreadsheet?

For a single value the field above is quicker, but for a whole column of measurements the spreadsheet does it with one formula dragged downwards.

  1. Excel: the CONVERT function

    The syntax is CONVERT(number, from_unit, to_unit). The centimeter is written "cm" and the kilometer "km", so for a value in cell A1 the formula reads =CONVERT(A1,"cm","km"). The prefixes c and k may be put in front of any metric unit argument[5].

  2. Plain division, if you would rather skip the function

    The formula =A1/100000 gives the same result and works in every spreadsheet, including Google Sheets and LibreOffice Calc. In the default General format Excel shows fewer decimal places so that the number fits the width of the cell, which can make the result for a few centimeters look rounded[6].

  3. More decimal places, or a power of ten

    To see the full result for a few centimeters, select the column and in Excel go to the Home tab, in the Number group, and click Increase Decimal until six places show. Picking Scientific from the number format list instead gives 4.50E-05, the same value written as a power of ten[7].

  4. Check the result on a single cell

    Before you drag the formula down the whole column, type 250000 into cell A1 and check that the result reads 2.5. A #VALUE! message where the result should be means Excel does not read the content of cell A1 as a number, for example when a unit has been typed next to the value. Leave just the number in the cell[5].

Convert other units to Kilometers

miles to kmmeters to kmmm to kmdm to kmau to kmyards to km

Convert Centimeters to other units

cm to pxcm to mmcm to dmcm to meterscm to feetcm to inchescm to yards

Sources

  1. Kilometre — Wikipedia
  2. SI prefixes — Bureau International des Poids et Mesures
  3. A Beginner’s Guide to Map Scales — Ordnance Survey
  4. US Topo: Maps for America — U.S. Geological Survey
  5. CONVERT function — Microsoft
  6. Stop showing rounded numbers — Microsoft
  7. Display numbers in scientific (exponential) notation — Microsoft

Every figure in the tables was computed from the unit definitions and checked arithmetically before publication. Historical values and the names of local units come from the sources listed above.

Content last reviewed: · written and checked by the Arteon team

Common questions about converting centimeters to kilometers

How many kilometers are in 1 centimeter?

A centimeter is 0.00001 kilometers. Written as a common fraction it is one hundred-thousandth of a kilometer, and in scientific notation 1 × 10⁻⁵ km.

How many kilometers are in 100,000 cm?

One hundred thousand centimeters make exactly one kilometer. Ten thousand centimeters gives 0.1 kilometers, and one thousand centimeters 0.01 kilometers.

How many kilometers are in 4.5 cm?

Four and a half centimeters is 0.000045 kilometers, that is 4.5 × 10⁻⁵ km. The same length written in meters comes to 0.045 m.

How do you read a ground distance off a length measured on a map?

You multiply the length you measured by the number after the colon and divide by one hundred thousand. Five centimeters on a 1:50,000 map gives 250,000 centimeters, and dividing brings that to 2.5 kilometers. Ready answers for three scales are in the table of measured lengths on this page.

How many kilometers are in 1 meter?

A meter is 0.001 kilometers, because a kilometer holds 1,000 meters. One hundred meters gives 0.1 kilometers, and five hundred meters 0.5 kilometers. A whole table of those values sits on the meters to kilometers converter.

Why does the divisor carry five zeros?

Because it takes five steps up the metric ladder to get from the centimeter to the kilometer, and each step multiplies the value by ten. On the way you pass four units, the decimeter, the meter, the dekameter and the hectometer, so 10 × 10 × 10 × 10 × 10 makes 100,000.

Will the tool show a result for just a few centimeters?

Yes. The result field carries up to seven decimal places, so 4.5 cm shows up as 0.000045 km and one millimeter, that is 0.1 cm, as 0.000001 km. You can type the value with a point or a comma, and as a simple fraction such as 1/2 as well.

Arteon free tool screenshot: Convert centimeters to kilometers

Have a question or suggestion?

If you spotted an error in the tables or have an idea to improve the converter, write to us — we reply within 24 hours.