Boat Trip Fuel, Maintenance and Profit Log with Service Hours

Boat Trip Fuel, Maintenance and Profit Log is an offline app (one HTML file in a zip) for the owner of one or several charter boats. For each trip you enter the income, the engine hours, the litres of fuel and the crew cost, and add extra costs such as ice, bait or marina fees. The app shows the margin on the trip. Each boat carries a fixed monthly cost and a service interval in engine hours, so the Boats page shows this month in full: income, trip costs, maintenance, fixed costs and profit, and how many engine hours are left before the next service.

The problem it removes: Whether a trip made money is never worked out. Fuel is bought in cash, crew are paid from the till, repairs are paid when something breaks, and the berth fee comes every month, so at the end of the month there is money in the drawer and no idea which boat or which kind of trip earned it. Engine services are remembered by feel, until an engine fails. This app puts income, costs and engine hours for every trip in one place.

What is inside:

• Boats with a monthly fixed cost, a service interval in engine hours and the engine hours at the start of your log
• Trips with income, engine hours, fuel litres at your fuel price, crew cost and any number of extra cost lines
• Margin per trip and per engine hour, and a loss flag when costs are higher than income
• Maintenance entries with cost and the engine hour reading at an engine service
• Per boat this month: income, trip costs, maintenance, fixed costs and profit
• Engine hours since the last service and hours left, with Due soon and Overdue states
• Printable trip cost sheet and a printable trips list for any period with totals
• Example data you can load in one click, a Start here guide and an Honest limits panel
• JSON backup and restore, CSV export, and CSV import with a check of every row before anything is added

Who it is for: owners of fishing boats, dhow and speedboat charters and small boat tour operators who keep their money in a notebook and want to know which trips and which boats earn a profit.

What it is NOT: It is not an accounting system. It does not know your tax position, does not post to any ledger, and does not give you maintenance rules: the service interval is a number you enter from your own engine manual or mechanic. It does not read engine meters, track fuel stock, or split income between boats on a shared trip. It is not legal, tax or accounting advice, it is not connected to any government system, bank or messaging service, and it does not file or send anything by itself. UAE e-invoicing is not part of it.

Your data stays on this device in your browser. Back it up with Export; clearing browser data loses it otherwise.

Verified by us: scripted tests in Chromium (139 checks through the real screens: adding, editing and deleting records in every table, required-field messages, backup then clear then restore, CSV export then import, keyboard order, print layouts rendered to PDF, no horizontal scrolling at 375 and 1280 pixels, no network requests) and an independent recalculation by a separately written Python evaluator of 1322 calculated values (25 randomised rows plus the example data) with 0 mismatches. Safari engine (WebKit): smoke test passed. Not tested: Firefox beyond what is stated here, and no real printer was used (print layouts were checked as PDF).