How this calculator works
The applied interval starts from your recommended interval, then gets cut in half if you selected severe conditions, because oil breaks down faster under that kind of stress. Subtracting the distance you've already driven since the last change tells you how far is left.
More detail
What counts as severe driving
Manufacturers generally define severe conditions as: frequent short trips under about 8 km (the engine never fully warms up), stop-and-go city traffic or long idling, driving on unpaved or dusty roads, towing or carrying heavy loads, or extreme heat and cold. Any one of these speeds up oil breakdown, which is why shops commonly recommend cutting the interval in half rather than using the standard schedule.
When in doubt. If your driving mixes normal and severe conditions — say, mostly short city commutes with occasional highway trips — lean toward the severe-condition interval. An early oil change costs far less than the engine wear from running degraded oil too long.
Frequently asked questions
I've driven 12,000 km, my last change was at 8,000 km, and my interval is 10,000 km — how far do I have left?
Under normal conditions: 4,000 km already driven since the last change, leaving 6,000 km until the next one (target odometer 18,000 km).
How does that change under severe conditions?
The 10,000 km interval is halved to 5,000 km. With 4,000 km already driven, only 1,000 km remains before the next change (target odometer 13,000 km).
What if the remaining distance shows a negative number?
A negative remaining distance means you've already passed the recommended change point — the calculator shows how far past it you are so you know to get it done as soon as possible.