Sri Lanka Fuel Cost Calculator (Petrol & Diesel Trip Cost)
Estimate the petrol or diesel cost of any trip in Sri Lanka. Enter distance, your vehicle's fuel economy and pick a CPC fuel grade — you get total litres, total cost, cost per km and a full four-grade comparison. Prices verified against the Ceylon Petroleum Corporation retail notice on 2026-06-02.
How it works
The calculator combines two figures — how far you're going and how efficiently your vehicle converts fuel into kilometres — with the current Ceylon Petroleum Corporation retail price for the fuel grade you select. The math is short, but the numbers underneath have to be right, which is why prices are cross-checked against the CPC retail notice in effect at 2026-06-02and the input is editable so the tool stays useful between CPC's monthly revisions.
- Effective distance.If you tick “round trip,” the entered distance is doubled. Everything below uses the effective distance, not the one-way figure.
- Normalise fuel economy. You enter either km per litre (Sri Lankan owner-manual standard) or litres per 100 km (European standard). The tool converts internally so the math is identical either way:
L/100km = 100 ÷ km/L. - Litres needed.
litres = (L/100km × effective distance) ÷ 100. This is mathematically identical toeffective distance ÷ km/L— the calculator computes both forms internally as a cross-check. - Total cost.
total = litres × price per litre. The price defaults to the CPC retail figure for the selected grade and you can override it whenever CPC revises prices. - Cost per km and per passenger. Total cost ÷ effective distance gives the per-km figure (used for billing client mileage). Total ÷ passengers gives a per-passenger split — useful for ride-shares and out-of-Colombo trips.
CPC publishes four passenger fuel grades — Lanka Petrol 92 Octane (the everyday grade), Lanka Super Petrol 95 Octane (turbocharged and high-compression engines), Lanka Auto Diesel (cars, vans, lorries, buses) and Lanka Super Diesel (low-sulphur for modern common-rail diesels). Prices revise on the 1st of each month under the cost-reflective formula approved by the Public Utilities Commission of Sri Lanka. The Lanka IOC notices, which are published alongside CPC's, match within ±LKR 1.
The comparison table at the bottom of the calculator runs the same trip across all four grades at your fuel economy figure, so you can see how a switch from Petrol 92 to Petrol 95 or from Auto Diesel to Super Diesel changes the bottom line. Note that real diesel vehicles almost always achieve better km/L than petrol vehicles of similar size — if you're costing a diesel trip, enter the diesel economy figure (the calculator can't guess engine type from fuel grade).
Worked examples
Frequently asked questions
Sources & references
- Ceylon Petroleum Corporation — official retail price notice
- Public Utilities Commission of Sri Lanka — fuel pricing formula
- Lanka IOC (LIOC) — secondary price publisher
- Sri Lanka Sustainable Energy Authority — vehicle fuel-economy data
Prices verified on 2026-06-02
- Petrol 92: Rs 434/L
- Petrol 95: Rs 495/L
- Auto Diesel: Rs 407/L
- Super Diesel: Rs 478/L
CPC revises retail prices on the 1st of each month. If the figures above are stale, override the price field on the calculator with the current pump price — the math still works.
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Comments & feedback
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