Convert cm³ to ml cubic centimetres ↔ millilitres Free Online Secure
Type a value in cubic centimetres and read it in millilitres at once. The factor is exact by definition, the arithmetic happens in your browser, and nothing is sent anywhere.
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Common values — Convert cm³ to ml (cubic centimetres ↔ millilitres)
| cm³ | ml |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 5 | 5 |
| 10 | 10 |
| 20 | 20 |
| 50 | 50 |
| 100 | 100 |
Where these units come from
The litre has an awkward history. From 1901 it was defined as the volume of one kilogram of pure water at its densest, which sounds elegant but came out at 1.000028 cubic decimetres — close enough to be confusing and far enough to spoil careful work. In 1964 the definition was abandoned and the litre became exactly one cubic decimetre, which it has been ever since. The gallon has a messier story still: the US gallon descends from the English wine gallon of 231 cubic inches, while Britain redefined its own in 1824 as the volume of ten pounds of water. Nobody reconciled the two, so a US gallon is 3.785411784 litres and an imperial gallon 4.54609 — about a fifth larger. The gallon, pint, cup, fluid ounce and spoons on this page are the US ones.
Where you meet them
Millilitres and litres run through daily life almost invisibly: bottles, fuel, paint, dosage, the capacity of a kettle. Cubic metres belong to water bills, concrete, shipping and the air a ventilation system has to move. Cubic centimetres name engine displacement, cubic feet appear in freight and in appliance capacities, and cups and spoons live almost entirely in recipes — which is exactly where the difference between a US cup and a metric one quietly ruins a cake.
Questions people ask
What does cc mean on an engine?
It stands for cubic centimetres, the same as cm³, and it states the engine's displacement: the total volume swept by its pistons. A 1600 cc engine is a 1.6 litre engine. The figure is a measure of size and not of power, since two engines of the same displacement can differ greatly in output.
Is a millilitre the same as a cubic centimetre?
Yes, exactly. Since 1964 the litre has been defined as one cubic decimetre, so a millilitre is exactly one cubic centimetre. Before that the litre was very slightly larger, by about 28 parts in a million, which is why very old tables show a tiny difference. Today you can swap them freely.
Is the answer exact?
Where both units are defined in terms of one another by whole numbers, yes — the page says so above the figure, and the only rounding is in how many digits are shown. Where the ratio has no finite decimal, the page shows twelve significant digits and says the relation is approximate rather than pretending otherwise.
Does anything I type leave my device?
No. The arithmetic runs in your browser; nothing is uploaded and there is no server to upload it to. Load the page once and it keeps working with the network switched off.
Flasks, burettes and density bottles: one cubic centimetre, one millilitre
In a chemistry lab the glassware is marked in millilitres, while a density table lists grams per cubic centimetre. Both refer to the same volume, so there is nothing to calculate: to convert cm³ to ml you keep the number and change only the unit. A 25 cm³ pipette delivers 25 mL, a density of 0.789 g/cm³ for ethanol is 0.789 g/mL, and 0.5 cm³ is 0.5 mL. This page shows the result as you type, and the text below explains why the two units are identical, where each one is used and what really matters in practice, which is the accuracy of the measurement.
You will find the rule with examples, a note on each unit, a comparison, a tour of laboratory situations and the slips to avoid. All arithmetic happens in your browser; nothing you enter is sent anywhere.
How to convert cm³ to ml: the factor is 1
The rule
A litre is exactly one cubic decimetre, or 1,000 cm³, and a millilitre is a thousandth of a litre. So a millilitre is exactly one cubic centimetre. To convert cm³ to ml, copy the number and change the unit: 5 cm³ is 5 mL, 37.5 cm³ is 37.5 mL and 0.2 cm³ is 0.2 mL. The same works backwards, from mL to cm³.
Worked examples
A 100 mL volumetric flask holds 100 cm³. A cube of 3 by 3 by 3 cm contains 27 cm³, which would hold 27 mL of water. A sample that raises the water in a measuring cylinder from 40 mL to 52 mL has a volume of 12 cm³.
Why there is nothing to multiply
Most conversion pages need a factor, such as 0.061 for cubic inches or 1,000 for litres. Here the two units are the same size. The difference is only convention: cubic centimetres come from geometry, millilitres from the measuring of liquids.
A quick check
After you convert cm³ to ml, the number must be exactly the one you started with. If it changed, a factor of 1,000 or 0.001 slipped in, and you have moved to litres or microlitres.
The cubic centimetre
A cube one centimetre on a side
The cubic centimetre is the volume of a cube 1 cm by 1 cm by 1 cm. It is the natural unit when a volume comes from lengths measured with a ruler, and it appears in density, in engine capacity and in materials data.
Where it appears
Density tables, solid samples, mechanical specifications and school geometry.
The millilitre
A thousandth of a litre
The millilitre is one thousandth of a litre, written mL or ml. It is the standard unit for liquid volumes in a laboratory: pipettes, burettes, flasks, measuring cylinders and reagent bottles are all graduated in it.
Where it appears
Glassware, reagent recipes, solution preparation and product labels.
Cubic centimetre and millilitre compared
The two units are the same volume. Scientists tend to write cm³ when a volume is derived from a solid or from geometry and mL when it is a liquid measured in a vessel. A protocol may say 10 cm³ in one step and 10 mL in the next, and nothing changes.
Before 1964, the litre was slightly larger than a cubic decimetre, by 28 parts per million, so old tables show a tiny difference. Since the redefinition the equality is exact, and for any practical lab work it was always negligible.
Where the conversion appears
Glassware and its tolerance
Glassware is sold with a stated tolerance. A good 100 mL volumetric flask is accurate to about 0.1 mL, so you can rely on 100 cm³ to a tenth of a percent. A 25 mL burette is good to about 0.03 mL. A simple beaker with graduations may be off by 5 percent, so its marks are only a guide.
Density
Density is mass per volume. Water at 20 °C has 0.9982 g/cm³, equal to 0.9982 g/mL. Ethanol has 0.789, mercury 13.55 and aluminium 2.70. Because the two volume units match, the same table works in both languages, and you never have to convert cm³ to ml before using it.
Dilution
The formula C1 × V1 = C2 × V2 only needs the two volumes in the same unit. Diluting 10 mL of a 2 M solution to 100 mL gives 0.2 M. Whether you write 10 mL or 10 cm³ makes no difference to the result, so long as you do not mix in litres without care.
Water is not exactly one gram per millilitre
The density of water peaks at 0.99997 g/cm³ at 4 °C and falls to 0.9982 at 20 °C and 0.9970 at 25 °C. A 100 mL sample at 20 °C therefore weighs 99.82 g. Chemists use these figures to calibrate pipettes and flasks by weighing water. The conversion from cm³ to mL does not change with temperature, but the mass and the volume of the water itself do.
Serial dilutions
In a serial dilution you transfer 1 mL of sample into 9 mL of diluent, giving 10 mL in total and a tenfold dilution. Repeating the step six times reaches one in a million. Each tube holds 10 cm³, and each transfer is 1 cm³. Microbiologists use the pattern to count bacteria, and the volumes are written in mL or cm³ interchangeably. The only thing that matters is that the same unit is used in every step, or you will convert cm³ to ml unnecessarily at each stage.
Spreadsheet use
If length, width and height are in columns A to C in centimetres, =A2*B2*C2 gives the volume in cm³, which is also the volume in mL. For a cylinder, =PI()*(A2/2)^2*B2. No further factor is needed. Format with the number of decimals that matches the instrument: two for a burette, one for a cylinder, none for a beaker.
Significant figures
A 50 mL cylinder is read to 0.5 mL, so a volume of 37.5 mL has three significant figures. As 37.5 cm³ it has the same three. Do not add digits when you change the symbol. In calculations, carry one extra digit through the steps and round at the end, as the rules for significant figures require.
Cell culture and small volumes
Cell biologists work with volumes such as 0.5 mL or 2 mL in a well plate. A well of 2 mL holds 2 cm³ of medium. When a methods section says 500 µL, that is 0.5 mL and 0.5 cm³. In these fields, a mistake of a factor of 10 or 1,000 is the usual error, and the identity between cm³ and mL is the one fact that is never in doubt.
Reference values
0.1 cm³ is 0.1 mL, 1 cm³ is 1 mL, 5 cm³ are 5 mL, 25 cm³ are 25 mL, 100 cm³ are 100 mL, 250 cm³ are 250 mL, 500 cm³ are 500 mL and 1,000 cm³ are 1,000 mL, one litre. If a result differs from the number you typed, check for a stray factor.
Checking a pipette by weighing
To test a 10 mL pipette, deliver it into a weighed beaker and weigh again. At 20 °C, 10 cm³ of water weighs 9.982 g, so a reading of 9.98 g confirms the delivery. A reading of 9.90 g means the pipette delivered 9.92 cm³, an error of 0.8 percent. This is how laboratories check glassware, and it works because 1 mL of water is almost exactly 1 g and 1 mL equals 1 cm³.
Checking your work
After you convert cm³ to ml, read the line aloud with the unit: five cubic centimetres, five millilitres. They sound different but are the same amount. For a more demanding check, compare with a density: 12 cm³ of a metal weighing 32 g has 2.67 g/cm³, near aluminium. If the number does not match any plausible material, a volume has probably been read or recorded wrongly.
Reagent bottles and headspace
A 500 mL reagent bottle is never filled to the neck. Safe storage leaves about 10 to 20 percent as headspace, so the working capacity is closer to 400 or 450 cm³. A 1 L bottle holds 800 to 900 mL of liquid. The bottle label shows the nominal volume, and the volume you can use is lower. Anyone who plans how many bottles are needed must account for this before they convert cm³ to ml the stock figures.
Buoyancy and the cubic centimetre
An object of 1 cm³ that is fully submerged in water displaces 1 cm³ of water, which weighs about 1 g. It floats if its mass is less than that, so a wooden cube of 1 cm³ with a density of 0.6 g/cm³ weighs 0.6 g and floats with 60 percent of its volume underwater. Students use cubes of known volume to check the rule, since the volume in cm³ is also the mass of displaced water in grams.
Measuring cylinders and their error
A class A measuring cylinder of 100 mL is typically accurate to about 0.5 to 1 mL, so a reading of 60 cm³ is really 60 plus or minus 0.5. A 10 mL cylinder is accurate to 0.1 mL, which is 1 percent at full scale but 10 percent at 1 mL. Choose the smallest cylinder that holds the volume, because the relative error shrinks as the reading approaches the top of the scale.
Thermal expansion
Liquids expand when heated. Water at 20 °C has a density of 0.9982 g/mL, and at 80 °C it is 0.9718. A volume of 100 mL at 20 °C becomes about 102.7 mL at 80 °C. Glassware is calibrated at 20 °C, so a hot solution is cooled before it is made up to the mark. The relationship between cm³ and mL stays exactly 1, but the volume of the sample is not constant.
For precise work, record the temperature next to each volume.
Writing volumes in a notebook
Good notebooks write the number, the unit and the instrument: 25.00 mL (burette), 10.0 cm³ (pipette), 50 mL (cylinder). When a colleague reads it later, there is no doubt about the precision. If you must convert cm³ to ml for a report, copy the number unchanged and keep the original unit in brackets, so an audit can trace every figure to the page where it was first recorded.
A short exercise
Measure a cube of aluminium that is 2 cm on each side. Its volume is 8 cm³, so it displaces 8 mL of water. With a density of 2.70 g/cm³ it weighs 21.6 g. Now drop it into a cylinder holding 50 mL of water: the level should rise to 58 mL. If you convert cm³ to ml the volume you calculated, the answer is 8 mL, and the experiment confirms it. Students gain confidence when the two routes agree.
The microlitre and the cubic millimetre
A microlitre is a millionth of a litre, which is exactly one cubic millimetre. A millilitre therefore holds 1,000 microlitres and 1,000 cubic millimetres. This ladder makes it easy to convert between very small volumes, as in micropipettes: 50 µL is 0.05 mL, 0.05 cm³ and 50 mm³. All of these are one and the same amount.
Measuring a solid by displacement
Place 40 mL of water in a graduated cylinder. Lower a stone in; the level rises to 52 mL. The stone has a volume of 12 mL, which is 12 cm³. With a mass of 31.8 g, its density is 2.65 g/cm³, matching quartz. The experiment links the two units in a single step and shows why a volume in mL can be used directly as a volume in cm³ in the density formula.
Pycnometers
A pycnometer is a small flask of precisely known volume, such as 25.000 cm³, used to measure density. Weigh it empty, filled with water and filled with the sample. The mass of the sample divided by 25.000 gives its density in g/cm³, the same as g/mL. Because the flask is labelled in cubic centimetres or millilitres, depending on the maker, a student sometimes wonders whether a correction is needed. It is not.
Preparing a solution
To make 250 mL of a 0.1 M salt solution, dissolve 1.461 g of sodium chloride, which is 0.025 mol at 58.44 g/mol, and make up to the 250 mL mark. The flask is graduated to 250 cm³, and the two labels mean the same. If your protocol says to prepare 250 cm³, use the same flask. When a recipe and a flask use different symbols, you do not need to convert cm³ to ml before starting.
Titration readings
A burette is read to 0.01 mL, though the scale shows 0.1 mL divisions. A titre of 23.45 mL is also 23.45 cm³. Differences between two readings give the volume delivered. Take the reading at the bottom of the meniscus, with your eye level with it, and repeat until two results agree within 0.1 mL. The conversion adds no uncertainty; the reading does.
Class A and class B glassware
Class A glassware has tighter tolerances than class B, typically by a factor of two. A 10 mL volumetric pipette in class A is accurate to about 0.02 mL, so its delivery of 10 cm³ is known to 0.2 percent. Class B might be 0.04 mL. The cost is higher for class A, but for analytical work the difference in uncertainty outweighs the price.
Percent weight per volume
A solution labelled 5 percent w/v contains 5 g per 100 mL, equal to 5 g per 100 cm³. Over a litre, 50 g. The percentage depends on volume, so a different temperature changes it slightly. In pharmacy and food laboratories both mL and cm³ appear in the same standard, and the identity of the two units keeps the formula simple.
More values for convert cm³ to ml
A longer list of conversions
If the value you need is not in the first list, these further conversions may be close enough to read off directly:
- 0.1 cm³ = 0.1 ml
- 0.5 cm³ = 0.5 ml
- 3 cm³ = 3 ml
- 4 cm³ = 4 ml
- 7 cm³ = 7 ml
- 15 cm³ = 15 ml
- 20 cm³ = 20 ml
- 75 cm³ = 75 ml
- 200 cm³ = 200 ml
- 500 cm³ = 500 ml
- 2,000 cm³ = 2,000 ml
- 10,000 cm³ = 10,000 ml
Mistakes when you convert cm³ to ml
Applying a factor
There is none. If you multiplied by 1,000 or divided by 1,000, you changed to litres or microlitres.
Confusing mL with L
0.75 mL and 0.75 L differ by a factor of 1,000. Write the unit on every line of a notebook.
Assuming glassware is exact
A beaker's marks are approximate. Use a volumetric flask or pipette when the volume matters.
Quick answers
How many millilitres are in a cubic centimetre?
Exactly one.
How do I convert cm³ to ml?
Keep the number and change the unit.
How many cubic centimetres are in a millilitre?
Exactly one.
What is 250 cm³ in millilitres?
250 mL.
Is the number I type uploaded?
No, it stays in your browser.
Related pages and a last word
If you work with volumes, these conversions are close at hand: Convert cm³ to L, Convert cm³ to m³, Convert tbsp to ml, Convert tsp to ml, Convert ml to tbsp, Convert km to mi, Convert mi to km, Convert °C to °F, Convert °F to °C. The reverse of this page is Convert ml to cm³.
To sum up: to convert cm³ to ml, keep the number, because a cubic centimetre is a millilitre, and write the unit beside the result. The figure you enter is processed locally, with no account and no upload.