Calq.

CBM Calculator

Calculate the total volume (CBM) and weight of your shipment with our easy-to-use CBM calculator.

Total Shipment Volume

m³

Introduction

The CBM Calculator from Calq. helps you work out the total volume (in cubic meters) and total weight of shipments made up of multiple packages. CBM stands for Cubic Meter, a standard metric measure of volume used by freight carriers. Knowing your shipment’s CBM is essential because many services charge by volumetric (dimensional) weight when cargo is light but bulky. This tool is designed for shippers, e-commerce sellers, warehouse teams, and freight forwarders who need fast, reliable pre-quote numbers.

How it works

  1. Choose your unit system: metric (cm or m) as primary, or imperial (inches or feet) as secondary.
  2. For each package type, enter length, width, height, quantity, and weight per package.
  3. Add more rows for different package sizes.
  4. The tool calculates CBM per package, total CBM for the shipment, and total actual weight.
  5. Use the totals to anticipate costs or to share dimensions with your carrier.

Inputs explained

  • Unit system: Select cm/m for metric or in/ft for imperial. Metric is standard in global freight.
  • Length, width, height: External dimensions of each box or pallet. Measure the longest points, including bulges, straps, or overhang.
  • Quantity: Number of identical packages with the same dimensions.
  • Weight per package: The gross weight of one package, including packaging, in kg (primary) or lbs (secondary).

Results and interpretation

  • CBM per package: The volume of one package in cubic meters.
  • Total CBM: The sum of all package volumes. This is the key number for space planning and for ocean freight LCL pricing.
  • Total weight: The actual mass of the entire shipment. Carriers compare this to volumetric weight when setting the “chargeable weight.”

Tip: Density (kg per m³) = total weight ÷ total CBM. Low density suggests you may be billed by volume rather than actual weight.

Method and assumptions

Formulas by unit:

  • If you enter cm: CBM per package = (Length × Width × Height) ÷ 1,000,000
  • If you enter m: CBM per package = Length × Width × Height
  • If you enter inches: CBM per package = (Length × Width × Height) × 0.000016387064
  • If you enter feet: CBM per package = (Length × Width × Height) × 0.0283168466
  • Total CBM = sum of CBM per package × quantity for each line
  • Total weight (kg) = sum of (weight per package × quantity). If entered in lbs, the calculator converts using 1 lb = 0.45359237 kg

About volumetric weight (for context):

  • Air freight (typical): Volumetric weight (kg) ≈ CBM × 167
  • Express couriers (common international divisor 5,000 cm³/kg): Volumetric weight (kg) ≈ CBM × 200
  • Road freight: Conversions vary by carrier and country (often 250-333 kg per m³).
  • Ocean LCL: Charges often use “W/M” (weight or measure). Chargeable units = the greater of weight in metric tons (1,000 kg) or volume in CBM.

⚠️ Important: Divisors and rules vary by carrier, service, and route. Treat the above as industry-standard guidelines and confirm with your provider.

Assumptions and limitations:

  • Dimensions are treated as rectangular prisms. Irregular shapes should be measured at their maximum length, width, and height.
  • Palletization, stacking allowances, and void space are not automatically included unless you input pallet dimensions as a separate line.
  • Results are estimates for planning and are not a freight quote.

Domain context: how CBM affects shipping costs

  • Air and express: You pay for whichever is higher-actual weight or volumetric weight. Bulky, light items often incur dimensional charges.
  • Ocean LCL: Pricing is typically per CBM, with a weight threshold at 1 metric ton per CBM for W/M comparisons.
  • Full containers: As a rough planning guide, a 20 ft container holds about 33 m³, a standard 40 ft about 67 m³, and a 40 ft high cube about 76 m³. Usable space is less after allowing for packaging and loading patterns. Always check specifics with your forwarder.
  • Road freight: Many carriers convert CBM to a “chargeable weight” using their own kg/m³ factor.

Tips and strategies

  • Measure the outside of the package, not the product. Include any bulges, straps, or corner protectors.
  • Round up dimensions to the nearest whole centimeter or quarter inch to avoid underestimation.
  • If shipping on pallets, add each pallet as its own line using the full pallet footprint and stacked height.
  • Group identical cartons into one line to reduce data entry time.
  • Compare density to common conversion factors. If density is lower than the carrier’s kg/m³ threshold, expect volumetric charges.
  • Keep a margin. Carriers often re-measure; a small buffer reduces surprise adjustments.

Example calculations

Example 1 (metric cartons)

  • Details: 8 cartons, each 60 cm × 40 cm × 35 cm, weight per carton 12 kg.
  • CBM per carton = (60 × 40 × 35) ÷ 1,000,000 = 0.084 m³
  • Total CBM = 0.084 × 8 = 0.672 m³
  • Total weight = 12 × 8 = 96 kg
  • Density = 96 ÷ 0.672 ≈ 143 kg/m³

Context: For air freight, indicative volumetric weight ≈ 0.672 × 167 = 112.2 kg, which is higher than 96 kg, so dimensional charges may apply. For ocean LCL W/M, compare 0.672 CBM vs 0.096 metric tons; 0.672 CBM is chargeable.

Example 2 (imperial boxes)

  • Details: 4 boxes, each 24 in × 20 in × 16 in, weight per box 30 lb.
  • Volume per box = 24 × 20 × 16 = 7,680 in³
  • CBM per box = 7,680 × 0.000016387064 ≈ 0.1259 m³
  • Total CBM ≈ 0.1259 × 4 = 0.5034 m³
  • Total weight in kg = 30 × 4 × 0.45359237 ≈ 54.4 kg
  • Density ≈ 54.4 ÷ 0.5034 ≈ 108 kg/m³

Context: Indicative air volumetric weight ≈ 0.5034 × 167 = 84.1 kg; express courier at a 5,000 cm³/kg divisor ≈ 0.5034 × 200 = 100.7 kg. Carriers bill the higher of actual vs volumetric weight per their rules.

Frequently asked questions

  1. What is CBM?
    CBM means Cubic Meter. It measures how much space your shipment occupies. Carriers use it for capacity planning and, together with weight, to determine charges.

  2. Do I measure inside or outside the box?
    Measure the outside dimensions, including any bulges, straps, or pallet overhang. Carriers charge on the space your freight actually takes up.

  3. Should I include the pallet?
    Yes, if shipping on pallets. Enter each pallet’s footprint and stacked height as a separate line to get an accurate total CBM.

  4. What is volumetric (dimensional) weight?
    It is a billing weight based on volume. For example, air freight often uses CBM × 167 to convert volume to a “chargeable weight.” If that number is higher than the actual weight, you pay for the volumetric weight.

  5. Why do different carriers give different numbers?
    Dimensional factors (kg per m³ or divisors) vary by carrier, service, and route. Always verify the current factor in your quote.

  6. Can I use this to check container fit?
    Yes, as a planning aid. Compare your Total CBM to typical container capacities (about 33 m³ for 20 ft, 67 m³ for 40 ft, 76 m³ for 40 ft high cube). Actual usable space depends on loading patterns, packaging, and weight limits.

Summary

Use the CBM Calculator above to quickly determine CBM per package, total CBM, and total shipment weight. These numbers help you estimate space, understand when volumetric weight could apply, and communicate accurate data to carriers. Results are planning estimates; confirm divisors and charges with your freight provider before booking.