Cubic Meter & CBM Converter
Convert a known cubic metre or CBM value to metric capacity units, cubic feet, cubic yards, U.S. liquid units, Imperial units and an international acre-foot. Reverse any supported comparison back to cubic metres with the same exact factor.
- 20 exact volume units
- CBM equals m³
- BigInt rational arithmetic
- Decimal or significant-figure rounding
Convert Cubic Metres and CBM
Enter one nonnegative volume, choose a comparison unit and select the direction. The calculator treats CBM as another name for one cubic metre and rounds only the final display.
1 m³ converted through the exact international-foot definition.
Calculation Steps
- Use 1 ft³ = 0.028316846592 m³ exactly.
- Calculate 1 ÷ 0.028316846592 = 1953125000/55306341 ft³ exactly.
- The target is approximately 35.3146667215 ft³ in the comparison display.
- Round the final value once to six decimal places: 35.314667 ft³.
CBM and m³ represent the same volume. The exact unit factor is preserved; the approximation sign marks final display rounding.
All Volume Equivalents
Compact terminating values are shown exactly. Other comparison values are rounded to 12 significant figures and carry an approximation label.
| Unit | Equivalent volume | Display status |
|---|
How to Use This Cubic Meter and CBM Converter
- Enter the volume. Type a nonnegative decimal or scientific-notation value without commas or a unit symbol.
- Choose the comparison unit. Select the metric, cubic, U.S. liquid or Imperial unit paired with cubic metres.
- Choose the direction. Convert cubic metres or CBM to the selected unit, or convert the selected unit back to cubic metres.
- Set the display precision. Choose decimal places or significant figures, enter the count, and select a midpoint rounding rule.
- Press the convert button. Review the answer, exact fraction, cubic-metre base, calculation steps and complete equivalents table.
- Copy, switch or reset. Copy the active result, reverse the direction without reusing a rounded answer, or restore the 1 CBM to cubic feet example.
Zero is accepted because an empty or calculated volume may equal zero. A negative nonzero entry is rejected because ordinary physical volume is a magnitude. The Switch Direction button keeps your typed number and changes only which unit it represents. It never places the rounded result back into the input.
Cubic Meter and CBM Conversion Formula
Each supported unit has an exact factor expressed in cubic metres. For a cubic-metre input, divide by the selected unit's cubic-metre factor. For a selected-unit input, multiply by that factor.
One international foot equals exactly 0.3048 metre. Cubing this length definition gives one cubic foot as exactly 0.028316846592 m³. Therefore, one cubic metre equals the exact fraction 1953125000/55306341 ft³, approximately 35.3146667215 ft³.
Why the length factor is cubed
Volume has three length dimensions. A box measured in feet has length, width and height in feet, so the foot-to-metre factor applies three times. Using 0.3048 only once would convert a length, not a volume.
Metric prefixes follow the same rule. One centimetre is 0.01 metre, but one cubic centimetre is (0.01)³ m³, or exactly 0.000001 m³. This is why one cubic metre contains one million cubic centimetres.
Worked Cubic Meter and CBM Examples
Example 1: Convert 1 CBM to cubic feet
CBM means cubic metre, so start with exactly 1 m³. Divide by 0.028316846592 m³ per ft³. The result is exactly 1953125000/55306341 ft³, approximately 35.3146667215 ft³. Six decimal places give 35.314667 ft³.
Example 2: Convert 10 CBM to cubic yards
One cubic yard equals exactly 0.764554857984 m³. Divide 10 by this factor. The exact result is 19531250000/1493271207 yd³, approximately 13.0795061931 yd³.
Example 3: Convert 100 cubic feet to cubic metres
Multiply 100 ft³ by exactly 0.028316846592 m³ per ft³. The result is exactly 2.8316846592 m³, so it is also exactly 2.8316846592 CBM as a mathematical unit conversion.
Example 4: Convert 500 U.S. liquid gallons to cubic metres
One U.S. liquid gallon equals exactly 0.003785411784 m³. Multiply 500 by the factor. The result is exactly 1.892705892 m³. Do not use the Imperial-gallon factor for a U.S. liquid value.
Example 5: Convert 1 cubic metre to litres
One litre equals one cubic decimetre, exactly 0.001 m³. Divide 1 m³ by 0.001 m³ per litre. The result is exactly 1,000 L. The conversion is exact, though the original measured volume may still have uncertainty.
Common Cubic Meter and CBM Conversion Table
Exact values are marked as exact. Repeating decimal results are rounded to 12 significant figures for a compact reference.
| Starting volume | Converted volume | Status |
|---|---|---|
| 1 m³ / CBM | 1,000 L | Exact |
| 1 m³ / CBM | 1,000,000 cm³ | Exact |
| 1 m³ / CBM | 61,023.7440947 in³ | Rounded display |
| 1 m³ / CBM | 35.3146667215 ft³ | Rounded display |
| 1 m³ / CBM | 1.30795061931 yd³ | Rounded display |
| 1 m³ / CBM | 264.172052358 US gal | Rounded display |
| 1 m³ / CBM | 219.969248299 Imp gal | Rounded display |
| 1 ft³ | 0.028316846592 m³ | Exact |
| 1 yd³ | 0.764554857984 m³ | Exact |
| 100 L | 0.1 m³ / CBM | Exact |
| 1 international acre-ft | 1,233.48183754752 m³ | Exact |
What CBM Means
CBM is a common trade and logistics abbreviation for cubic metre. It does not define a second unit. One CBM equals one cubic metre exactly. The standard SI symbol remains m³.
A cubic metre is the volume of a cube measuring one metre on each side. It equals exactly one kilolitre, 1,000 litres, one million millilitres and one million cubic centimetres. Those identities come from the metric definitions, not from a measured substance.
CBM often appears on packing lists, freight quotes and warehouse records. In those settings, it normally describes cargo volume. It does not by itself state cargo mass, billable weight, price, usable container space or whether a shipment physically fits through an opening.
Cubic Units and Capacity Units
Cubic units describe three-dimensional space from a length unit raised to the third power. Capacity units such as litres and gallons also describe volume, but their names often come from liquid-measure systems. The converter places both types on one exact cubic-metre base.
- Metric cubic units: km³, m³, dm³, cm³ and mm³ follow cubed powers of ten.
- Metric capacity units: 1 kL equals 1 m³, 1 L equals 1 dm³, and 1 mL equals 1 cm³.
- International cubic units: in³, ft³, yd³ and acre-ft use the international inch, foot, yard and foot-derived area definitions.
- U.S. liquid units: gallons, quarts, pints and fluid ounces use the U.S. liquid system.
- Imperial units: gallons, quarts, pints and fluid ounces use the UK Imperial definition.
The bare words gallon, quart, pint and fluid ounce are incomplete because U.S. liquid and Imperial units differ. This page labels both systems throughout. It excludes generic cups, barrels and freight tons because those names need a specific definition before an exact conversion is possible.
Known CBM Versus Calculating Shipment CBM
This converter starts with a volume that is already known. It changes the unit only. If you have carton dimensions instead, first convert length, width and height to metres, multiply them, then multiply by a valid package quantity. The separate CBM Calculator handles that workflow.
An outside-dimension calculation gives a rectangular bounding volume. It does not guarantee usable internal capacity or container fit. Wall thickness, irregular shapes, packing orientation, pallets, clearance, door dimensions, stacking limits, weight limits and restricted cargo may change a real loading plan.
CBM also differs from volumetric weight. A carrier may apply a service-specific divisor or conversion rule, then compare a dimensional value with actual mass. This page does not apply a freight divisor, choose chargeable weight or estimate a shipping price.
Why CBM Does Not Directly Convert to Kilograms
Cubic metres measure volume. Kilograms and pounds measure mass. Converting between them requires the material's density under stated conditions.
One cubic metre of water is often described as about 1,000 kg, but this is not a universal CBM-to-kilogram factor. Air, timber, oil, steel and mixed cargo all have different densities. Temperature, pressure, composition, moisture and void space may also matter.
Use a verified density with compatible units when mass is needed. For freight, follow the carrier's published actual-weight and dimensional-weight rules instead of treating every CBM as one fixed mass.
Standard Gas Volumes Need Reference Conditions
Nm³, Sm³ and standard cubic feet are reference-condition gas volumes. Their meaning depends on a stated temperature, pressure and sometimes a gas-compressibility convention. Different industries and standards do not always use the same reference conditions.
This calculator therefore supports ordinary geometric m³, not an unstated normal or standard gas volume. Do not remove the N, S or standard label from a gas record and treat the number as directly interchangeable with an actual cubic metre at another condition.
Exact Factors and Useful Precision
The calculator parses the entered decimal as a fraction, applies an exact unit factor, reduces the result and rounds only the final display. Decimal-place mode fixes digits after the decimal point. Significant-figure mode keeps a selected count from the first nonzero digit.
- Nearest, ties to even sends an exact midpoint to the result whose retained final digit is even.
- Nearest, ties away from zero sends an exact midpoint to the result with greater magnitude.
- An equals sign marks a complete exact display.
- An approximation sign marks a display that discarded a nonzero part of the exact result.
An exact unit definition does not improve the accuracy of a measured input. Match the final digits to the measuring method, source record and purpose. Keep the unrounded exact value through later calculations and round once at the reporting step.
If a small nonzero result displays as zero, increase the decimal places or use significant figures. Exact zero has no first nonzero digit, so the calculator directs zero values to decimal-place mode.
Common Cubic Meter and CBM Conversion Mistakes
- Treating CBM and m³ as different units: they represent the same volume.
- Using a linear factor: cubic-foot and cubic-inch conversions require the third power of the length factor.
- Applying a metric prefix once: one cm³ is 10-6 m³, not 10-2 m³.
- Leaving a gallon system unstated: U.S. liquid and Imperial gallons have different exact sizes.
- Confusing outside volume with capacity: exterior dimensions do not prove usable internal space.
- Converting volume to mass without density: no universal CBM-to-kilogram factor exists.
- Using an unstated gas reference: Nm³, Sm³ and standard cubic feet need defined conditions.
- Rounding intermediate values: preserve the exact factor and round the final displayed answer once.
- Typing commas or symbols: enter 1000 rather than 1,000 m³ in the value field.
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Frequently Asked Questions
Is CBM the same as a cubic metre?
Yes. CBM is a common abbreviation for cubic metre. One CBM equals exactly 1 m³. The standard SI symbol is m³.
How many litres are in 1 CBM?
One CBM equals exactly 1,000 litres because 1 L equals exactly 0.001 m³.
How many cubic feet are in 1 CBM?
One CBM equals exactly 1953125000/55306341 ft³, approximately 35.3146667215 ft³.
What formula converts CBM to cubic feet?
Divide cubic metres by exactly 0.028316846592, or multiply by the exact fraction 1953125000/55306341.
How many cubic yards are in 1 CBM?
One CBM equals exactly 1953125000/1493271207 yd³, approximately 1.30795061931 yd³.
How many U.S. liquid gallons are in 1 CBM?
One CBM equals exactly 125000000000/473176473 US gal, approximately 264.172052358 US gal.
How many Imperial gallons are in 1 CBM?
One CBM equals exactly 100000000/454609 Imp gal, approximately 219.969248299 Imp gal.
Does this converter calculate CBM from box dimensions?
No. This page converts a volume that is already known. Use the separate CBM Calculator when you have length, width, height and package quantity.
Can I convert CBM directly to kilograms?
Not from volume alone. You need the material's density and compatible conditions to convert cubic metres into mass.
Does this tool convert Nm³, Sm³ or standard cubic feet?
No. Those gas-volume labels depend on stated reference temperature, pressure and sometimes other conventions. This tool converts ordinary geometric volume only.
Calculation Method and Review Basis
Metric volume relationships, international cubic-unit factors, U.S. liquid units and the international acre-foot were checked against NIST Handbook 44, 2026, Appendix C. SI symbols and the litre-to-cubic-metre relationship were checked against NIST SI Units: Volume and the BIPM SI Brochure, 9th edition. Imperial factors were checked against the UK Weights and Measures Act 1985, Schedule 1.
Measurement disclaimer: This page performs mathematical unit conversion. It does not certify cargo volume, vessel capacity, container fit, freight class, chargeable weight, gas reference volume, density, package declarations or legal-metrology results. Confirm the source measurement, unit system, reference conditions and reporting rule before consequential use.