How the DST matrix works
The tool applies this equation to three speed scenarios simultaneously, then adds the resulting duration to your base departure time to produce an ETA for each. Because the three scenarios share the same distance and departure, differences in arrival time come purely from the change in speed.
Eco vs standard vs full speed trade-offs
Bunker consumption rises roughly with the cube of speed, so a small speed reduction can produce a large fuel saving — at the cost of a later arrival. The matrix quantifies that time cost so a charterer, operator or bunker planner can weigh it against the fuel saving from slow steaming.
Reading the "vs Standard" column
Scenario B is treated as the baseline. A green "faster" badge on Scenario C shows how much time you gain by ordering full speed. A red "slower" badge on Scenario A shows how much time you give up by ordering eco speed. The baseline row itself always shows as neutral.
Bunker and weather considerations
This calculator uses fixed speed through water. It does not model head/tail currents, weather routing, sea margin, or port waiting time. For a firm voyage plan, apply an appropriate weather margin and cross-check the fuel estimate against the vessel's speed-consumption curve.
Frequently asked questions
What is a Distance-Speed-Time (DST) matrix?
A DST matrix compares multiple vessel speed scenarios against a single voyage distance so operators can see steaming time, ETA and the hours saved or lost at each speed in one view.
How is steaming time calculated?
Steaming time in hours equals voyage distance in nautical miles divided by speed in knots. The result is converted into days and hours for readability.
What is the difference between eco, standard and full speed?
Eco speed is a reduced steaming speed chosen to minimise bunker consumption. Standard speed is the vessel's typical charter-party speed. Full speed is the maximum sustainable speed used when schedule recovery matters more than fuel cost.
How is the 'vs Standard' column calculated?
For each scenario, the tool computes steaming time at Scenario B (Standard) minus steaming time at that scenario. A positive result means time saved (faster arrival); a negative result means time lost (later arrival).
Does the calculator account for weather, currents or port congestion?
No. The matrix assumes a constant speed through water with no external influences. Always add a weather and port margin when building the final voyage plan.