Is 100,000 miles on a 6 year old car bad?

No, 100,000 miles on a six-year-old car is not automatically bad. It works out to about 16,700 miles per year, which suggests fairly frequent use but does not establish the vehicle's condition. Consistent highway driving can be easier on some components than repeated short trips, although either driving pattern requires proper maintenance. Look for documented oil changes, transmission service when specified, cooling-system maintenance, and any timing-belt replacement required by the manufacturer. Check the tires, brakes, suspension, rust, and signs of leaks. An independent inspection can reveal whether expensive work is approaching. Compare the asking price with similar cars of the same year and mileage. A well-maintained 100,000-mile car can be a sensible purchase if its condition and price support it.