PortInsight.io › Demurrage calculator
Demurrage Calculator — Work Out Demurrage Charges
A free calculator for demurrage charges on containers and vessels. Enter free time or laytime, the daily rate and the expected delay, and it returns the demurrage exposure — with live port congestion figures from the ports PortInsight tracks folded into the delay estimate.
How demurrage is calculated
Demurrage is charged for time beyond the agreed free time (containers) or laytime (vessels). The basic formula is the same in both cases:
Demurrage charge = chargeable days beyond free time × daily rate × number of units
- Chargeable days — calendar days from the end of free time to the day the container is returned or the vessel completes cargo operations. Most carriers count part-days as full days.
- Daily rate — tariff rate for containers (often tiered, rising after the first few days) or the demurrage rate in the charter party for vessels.
- Units — number of containers, or one vessel.
Example: 12 containers, 5 days free time, released on day 9, tariff $95 per container per day → 4 chargeable days × $95 × 12 = $4,560.
Typical demurrage rates by vessel type
| Vessel type | Indicative hourly rate | Per day (24h) |
|---|---|---|
| LNG carrier | $750 | $18,000 |
| Crude / product tanker | $680 | $16,320 |
| Container ship | $520 | $12,480 |
| Bulk carrier | $450 | $10,800 |
| General cargo | $400 | $9,600 |
Rates are planning baselines drawn from published market references (Baltic Exchange, Clarksons Research 2024–25). Contracted rates vary with vessel size, charter party terms and freight market conditions.
Demurrage vs detention
Demurrage covers time the container or vessel sits inside the terminal beyond free time. Detention covers equipment kept outside the terminal — for example a container held at a warehouse after pickup. Both can run at the same time on different boxes of the same shipment.
Frequently asked questions about demurrage charges
What are demurrage charges?
Demurrage charges are the penalty a carrier or shipowner bills when cargo or a vessel occupies terminal time beyond the agreed free time or laytime. They compensate for the asset being unavailable for its next job.
How do you calculate demurrage per day?
Count the days past free time, multiply by the contracted daily rate, then multiply by the number of containers. Carriers usually charge a tiered rate that increases in steps after the first few chargeable days.
Who pays demurrage?
Under most container contracts the consignee or the party named on the bill of lading pays. Under a charter party it is normally the charterer, who may recover it from the shipper or receiver depending on terms.
How can demurrage be avoided?
Pre-clear customs, book haulage and empty return slots before the vessel arrives, negotiate longer free time on congested lanes, and watch anchorage queues so you know several days ahead that a berth window is slipping.
Is port congestion a valid reason to waive demurrage?
Sometimes. Many contracts and some regulators expect free time to be extended when the delay is outside the merchant's control and the container could not physically be collected. Documented congestion evidence — dated vessel wait times and berth occupancy — supports that claim.
How much is demurrage per container per day?
Typical container demurrage runs from roughly $75 to $300 per TEU per day depending on carrier, port and how many days have already elapsed, with rates escalating in later tiers.