What is laytime?
Laytime is the amount of time the shipowner agrees to make the vessel available at the load or discharge port without additional payment. It is defined in the Charter Party and typically expressed in running days, weather working days, or a fixed number of hours.
Demurrage vs despatch
If the charterer detains the vessel beyond the allowed laytime, they owe demurrage — liquidated damages at a daily rate. If cargo operations finish early, the shipowner typically rewards the charterer with despatch, historically set at half the demurrage rate.
How the calculation works
The calculator converts allowed and actual times to minutes, measures the difference, then multiplies the fractional days by either the demurrage or despatch rate depending on the sign of the difference.
Common laytime clauses
WWDSHINC (Weather Working Days, Sundays and Holidays Included) and SHEX (Sundays and Holidays Excepted) are among the most common laytime definitions. Always refer to the exact Charter Party wording — this tool is a quick preview, not a legal laytime statement.
Frequently asked questions
What is laytime?
Laytime is the period of time agreed in a Charter Party during which the shipowner makes the vessel available for loading or discharging cargo without extra payment.
What is demurrage?
Demurrage is liquidated damages payable by the charterer to the shipowner when the vessel is detained beyond the agreed allowed laytime.
What is despatch?
Despatch (or dispatch) is a reward paid by the shipowner to the charterer for completing loading or discharging faster than the allowed laytime.
How is demurrage calculated?
Take the extra time used beyond allowed laytime, convert it to days (including fractional days), and multiply by the agreed demurrage rate per day.
What is a typical despatch rate?
Despatch is traditionally set at half the demurrage rate, but the exact figure is negotiated in the Charter Party and can vary by trade and vessel type.