CBM Freight Planning Guide
A practical guide to calculating CBM for sea freight and air freight shipments. Covers carton and pallet measurement, LCL vs FCL planning, volumetric weight, and how shipping deadlines and working days fit into a logistics workflow.
What CBM means in freight planning
CBM — cubic metres — is the unit freight forwarders use to quote LCL sea freight and calculate chargeable weight for air freight. Before contacting a forwarder for a price, you need to know your total CBM. Without it, any quote you receive is an estimate at best, and you cannot accurately compare rates from different providers.
The calculation itself is straightforward: multiply the outer carton dimensions (length × width × height) and multiply by the number of cartons. If you have multiple carton types in one shipment, calculate each separately and sum the results. The CBM Calculator handles multiple product lines in one session.
CBM is also the starting point for a broader logistics planning workflow. Once you have your volume, you need a delivery date, a margin check on landed cost, and confirmation of the timeline in working days — all of which connect to other UtilityPilot calculators.
Key concepts
What you need to know before calculating CBM
Outer carton dimensions, not product dimensions
CBM is calculated from the outer shipping carton — the assembled box that goes into the container. Product dimensions, inner packaging, and dividers are irrelevant. Always measure the carton as it will be shipped, fully packed and sealed.
LCL vs FCL breakeven
LCL (Less than Container Load) consolidates multiple shippers into one container. A standard 20ft container holds roughly 25–28 CBM; a 40ft holds around 55–67 CBM. LCL is typically economical below 10–15 CBM. Above that, comparing FCL rates is worthwhile. The exact crossover depends on the trade lane and current market rates.
Palletised vs loose carton CBM
If goods ship on pallets, measure the pallet dimensions (including the pallet boards) rather than the individual cartons. Carriers charge on the space occupied by the pallet stack, not on the carton arrangement inside. A EUR pallet (120 × 80 cm) with 120 cm stacked height = 0.96 CBM per pallet.
Volumetric weight
Carriers charge whichever is greater: actual weight or volumetric weight. For sea freight, the standard conversion is 1 CBM = 1,000 kg volumetric weight. For air freight, 1 CBM = 167 kg (or 1 kg per 6,000 cm³). A lightweight but bulky shipment is likely to be charged on volume, not actual weight.
Origin and destination handling
CBM is used to quote the ocean or air leg only. Origin port handling (container freight station charges), customs clearance fees, destination port charges, and last-mile delivery are typically quoted separately. Always clarify which cost components are included in a CBM-based freight quote.
Mixed product lines
A shipment often contains multiple carton sizes. Calculate CBM separately for each product line (L × W × H × quantity) and sum the results. The CBM Calculator handles multiple product lines in a single session with mixed units.
Logistics workflow
From carton dimensions to delivery confirmation
CBM is the first number in a shipment planning workflow. Each step below links to the relevant calculator.
- 1
Measure outer carton dimensions
Measure length, width, and height of each shipping carton in cm (or another consistent unit). Record the quantity per carton type. These are the inputs the CBM Calculator needs.
CBM Calculator - 2
Calculate total CBM and volumetric weight
Enter dimensions and quantities to get total CBM and volumetric weight. Compare volumetric weight against actual weight to predict whether your freight will be volume- or weight-rated.
CBM Calculator - 3
Estimate delivery window
Once you have a departure date and transit time from your forwarder, use the Shipping Deadline Calculator to find the real estimated arrival date, accounting for cut-off times and public holidays in origin and destination countries.
Shipping Deadline Calculator - 4
Check the delivery date falls on a working day
Use the Real Due Date Calculator to confirm whether the estimated arrival date is an actual operating day. If a delivery falls on a weekend or public holiday, the real receiving date shifts forward.
Real Due Date Calculator - 5
Count working days in the shipping window
Use the Business Days Calculator to confirm lead times to customers or set internal milestone dates during the shipping window.
Business Days Calculator - 6
Check gross margin after adding freight
Once you have a freight cost per CBM from your forwarder, add it to your landed cost and run the Margin Calculator to confirm the product still meets your margin target.
Margin Calculator
Timing
Why shipping deadlines and working days matter in freight planning
Freight transit times are typically quoted in business days, not calendar days. A "10–14 business day" transit excludes weekends and public holidays in the origin and destination countries. The Shipping Deadline Calculator applies these exclusions automatically when you enter a dispatch date and transit time.
Cut-off times also affect the start of the transit window. Most freight forwarders have a daily cut-off (often mid-afternoon) after which an order is held until the next dispatch date. If a confirmed order arrives after the cut-off, your actual transit window starts one business day later than you might expect.
For cross-border shipments, origin and destination holiday calendars can both affect the timeline. A shipment from the UK to Germany near Christmas may encounter holiday delays at both ends. The Shipping Deadline Calculator merges both country calendars to produce a realistic delivery date.
Checking margin on landed cost
Once you have a CBM figure and a freight rate per CBM from your forwarder, add the freight cost to your product cost to get the total landed cost. Run the Margin Calculator to check whether your gross margin still meets your target after freight is included. For import pricing, also check the Markup Calculator to confirm your sell price from the landed cost.
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