How Many Tons of Charcoal Fit in a 20 ft and 40 ft Container, by Shape
By Mohamad Sinno, Charcoal Expert · Last updated
How many tons of charcoal fit in a 20 ft container depends on the shape ordered; a 40 ft does not. Figures below are for coconut shell charcoal briquettes, within container loading and sea freight for coconut charcoal.
The numbers, and the date they were confirmed
A 20 ft container of coconut shell charcoal briquettes loads 18.5 to 20 tonnes depending on the shape ordered; a 40 ft loads 26.5 tonnes for every shape. The container payload charcoal figures below, tons per 20ft by shape, were confirmed 24 July 2026.
Shape moves the 20 ft figure and leaves the 40 ft alone
A 20 ft fills to volume before it reaches its weight limit, so packing density — and therefore shape — sets its payload; a 40 ft weighs out first and lands on one figure whatever the shape. On a 20 ft it is cubic capacity — roughly 33 m³ (iContainers, 2026) — not the weight plate, that binds. So cube tonnage is a 20 ft variable — the hexagonal tonnage penalty runs 1.5 t against the highest-loading cube — and none on a 40 ft: weight limits vs volume.
The full payload matrix and the box math
Every shape ships in the same 10 kg net master carton, so the carton math and the payload are one figure twice over.
| Shape / size | 20 ft payload | 20 ft cartons | 40 ft payload | 40 ft cartons |
|---|---|---|---|---|
| Cube 25 mm, 26 mm | 20 t | 2,000 counted | 26.5 t | 2,650 |
| Cube 27 mm, 28 mm | 19.5 t | 1,950 counted | 26.5 t | 2,650 |
| Hexagonal, finger, flat/brix | 18.5 t | 1,850 | 26.5 t | 2,650 |
Only the cells marked counted are measured — 25/26 and 27/28 mm cube on a 20 ft. Every other cell is arithmetic on those and the constant master carton net weight, which is why the 40 ft columns repeat. Dome is absent deliberately: the factory makes it, but no dome load has been measured. A 20 ft is always floor-loaded; only a 40 ft takes ISPM-15 marked pallets, 20 per box — so pallet loss is a 40 ft question. That mark is a heat treatment on the timber, not a certification held here.
A compliant stow gives up volume before it gives up weight
The headspace a charcoal container keeps is a condition of carriage — this cargo ships as UN 1361, Class 4.2 — not a packing preference, so the cube it costs is not recoverable. IMDG Special Provision 978 grades it: 30 cm of headspace shall be maintained, then either stack height should stay under 1.5 m or blocks should cap at 16 m³ with 15 cm between them (SP 978.6 via CINS, September 2024) — the headspace binds regardless. On a 20 ft that costs cube the load would have used, part of why achieved payload sits below the rating. The stuffing sequence itself is in the 30 cm headspace and stack-height limits a compliant charcoal stow keeps.
Published charcoal payloads that fail their own check
The figures a buyer meets first do not survive checking. One widely cited article gives about 1,400 ten-kilo bags for a 20 ft and up to 2,800 for a 40 ft, then closes with 1,000–1,100 and 2,000–2,200 — unreconciled, in one document (read 30 July 2026). Its 40 ft figure also overshoots: 2,800 bags is 28,000 kg, and ISO 668:2020 Table 2 rates a 40 ft at 30 480 kg maximum gross mass, leaving about 26,730 kg after a typical 3,750 kg tare (Mobile Modular, 2026) — some 1,270 kg short. Heavier units exist under clause 5.2.2, tested and marked to their actual rating, though not always fully intermodal — but the article never says which box it assumes, and that is the defect. Forum answers beside it put a 20 ft at 27 t and at 21.7 t, one calling a payload a tare. Check a quoted tonnage against the plate, and against its source's other claims.
Worked example: choosing 20 ft or 40 ft for your order
20 t of 25 mm cube is exactly one 20 ft at 2,000 cartons; the same 20 t of hexagonal will not fit. Minimum order is one full container, so shape decides the box: 20 t of hexagonal needs 2,000 cartons and a 20 ft holds 1,850. Trim to 18.5 t, or step up to a 40 ft and take 2,650. Tons per 40ft, flat at 26.5 t, means the step buys 8 t. Production runs 15 working days for a 20 ft, 20 for a 40 ft; Indonesia-origin transit times by port pair covers the ocean leg. What tonnage does not decide is who declares the cargo: which incoterm makes the buyer the dangerous-goods declarant.
When the US road limit decides the equipment
A 40 ft at 26.5 t can clear everything at sea and still exceed what a road combination may legally carry inland, sometimes making the 20 ft the only workable box. Under the US 80,000 lb / 36,287 kg gross vehicle weight cap, OOCL recommends about 20.19 t for a 40 ft door move (OOCL, 2024) — six tonnes under a full load. Miss it and the box sits: free time, demurrage and detention once the box lands. To check how many tons of charcoal your order puts in a 20 ft or a 40 ft: WhatsApp +628213924038.
Payload figures are this factory's own loads for its own packing, not an industry constant; container ratings and road limits vary by unit and jurisdiction. Confirm the rating on the individual container's plate and the inland weight limit with your carrier or forwarder, and confirm SP 978 requirements with a licensed dangerous-goods specialist, before booking.