About this calculator
The TEU (twenty-foot equivalent unit) is the unit of container capacity: one 20-foot box = 1 TEU. An FEU (forty-foot equivalent unit) = 2 TEU. Container ship capacity, terminal throughput and slot rates are almost always quoted in TEU, while what is actually loaded is a mix of 20', 40', 40' high cube and sometimes 45' boxes.
This calculator adds the mix up with nominal length factors: 20' = 1 TEU, 40' and 40'HC = 2 TEU (height does not change TEU), 45' = 2.25 TEU, plus 10', 48' and 53' for special cases. You get total TEU, FEU, the number of boxes and the TEU-per-box ratio — the figure carriers use to estimate how many 20' and 40' slots a booking list needs. A ratio of 1.0 means all 20'; close to 2.0 means nearly all 40'.
Enter the nominal capacity of the ship or slot block to see utilisation and remaining TEU. The homogeneous capacity section answers the more honest question: how many TEU at an average 14 t the available cargo deadweight can really carry. A 1,000 TEU nominal ship often lifts only 600–700 TEU at 14 t. Remember that a 45' may take a 40' slot on board or need special positions on deck; each carrier has its own slot rules.
Worked example
Booking list: 120 × 20', 80 × 40', 60 × 40'HC, 10 × 45', ship of 500 TEU:
- TEU = 120 × 1 + 80 × 2 + 60 × 2 + 10 × 2.25 = 120 + 160 + 120 + 22.5 = 422.5 TEU (211.25 FEU)
- 270 boxes, TEU-per-box ratio 422.5 ÷ 270 = 1.565
- Utilisation 422.5 ÷ 500 = 84.5%, 77.5 TEU remaining
- Homogeneous capacity: 6,000 t cargo deadweight ÷ 14 t = 428 TEU (weight-limited, not slot-limited)
How to use it
Enter counts per size
Enter the number of 20', 40', 40'HC and 45' boxes (and special sizes if any) from the booking list or manifest.
Enter capacity (optional)
Enter the nominal ship capacity or slot allocation in TEU to see utilisation and remaining slots.
Check homogeneous capacity
Enter the available cargo deadweight and the average weight per TEU (usually 14 t) to see the weight limit.