Oil Change Interval Calculator
Track miles and months until your next oil change based on driving conditions and oil type.
What this calculates
Modern engines and synthetic oils last far longer than the old '3,000 miles' rule. Manufacturers now recommend 5,000-15,000 miles depending on oil type, with severe-service intervals roughly half that. This calculator tracks miles remaining and time until the next service.
Formula & how it works
Miles remaining = recommended interval − miles since last change. Months remaining = recommended months − months since last change. Service due = whichever hits zero first.
Worked example
Synthetic 7,500 mi interval, last changed at 45,000 mi 4 months ago. Now at 49,200 mi. Miles remaining: 3,300. Months remaining: 8. Service due in ~3,300 mi.
Frequently asked questions
Conventional vs synthetic?
Conventional: 3,000-5,000 mi. Synthetic blend: 5,000-7,500. Full synthetic: 7,500-15,000. Always defer to your owner's manual.
What is severe service?
Short trips (<10 mi), extreme temperatures, dusty roads, towing, or stop-and-go. Halve the normal interval.
Time matters too?
Yes — oil oxidizes even when parked. 6-12 months is the typical time-based cap regardless of mileage.