A voyage fuel estimate you can check
Build a traceable voyage fuel estimate from distance, speed, burn rate and price, with a worked example and a review checklist.
Start with the inputs, not a total
A useful estimate can be reconstructed by another person. Record the intended route distance in nautical miles, planned speed in knots, consumption at that speed, fuel unit, price unit and the date of the price. Keep the route and vessel assumptions beside the result. A straight-line distance is not a substitute for a reviewed passage route.
Work the arithmetic
For an illustrative 120-nautical-mile passage at a constant 10 knots, underway time is 12 hours. At an assumed 40 litres per hour, the underway fuel estimate is 480 litres. At an assumed €1.20 per litre, the fuel cost is €576. These are invented teaching inputs, not a SeaWise route result, fuel quote or promise of vessel performance.
Account for what the example leaves out
The simple calculation excludes manoeuvring, waiting, generators, weather, current and the vessel’s reserve policy. Add these as explicit line items using vessel-specific evidence and the responsible skipper’s plan. Do not hide a reserve inside the burn rate: the next reviewer needs to distinguish expected consumption from fuel held back.
Check units before comparing options
Keep litres, US gallons and imperial gallons separate. A bunker price per metric tonne cannot be compared directly with a price per litre without a suitable density conversion and a clear fuel specification. Record taxes, delivery fees, minimum order and validity when using an actual supplier quotation.
Use SeaWise as an estimation workspace
SeaWise combines port-to-port route planning, vessel fuel curves and fuel cost calculations. Review the generated route and inputs before relying on an estimate. Reconcile the plan with actual consumption after the voyage so future vessel assumptions improve. SeaWise estimates support planning; they do not replace charts, navigational judgement or supplier confirmation.