California speed limits, explained
The limit isn't just the number on the sign. Learn the Basic Speed Law and every California limit — and the right answer on the DMV test.
In California, the speed limit isn't just the number on the sign. The Basic Speed Law comes first: you may never drive faster than is safe for the conditions — even when you're under the posted limit. This guide explains the Basic Speed Law, California's maximum limits, the 25 and 15 mph prima facie limits, and school zones, so you drive legally and answer the speed questions on the DMV knowledge test.
The Basic Speed Law (the master rule)
California's Basic Speed Law says you may never drive faster than is safe for current conditions — no matter what the sign says. In rain, fog, heavy traffic, or near pedestrians, the safe speed may be well below the posted limit. Driving the posted speed in unsafe conditions can still get you a ticket.
Maximum speed limits
The maximum speed limit on most California highways is 65 mph. You may drive 70 mph only where posted. On a two-lane undivided highway the limit is 55 mph unless otherwise posted — and 55 mph is also the limit when towing a trailer, and for buses and trucks with three or more axles.
Prima facie limits: 25 and 15 mph
Where no sign is posted, California's prima facie limits apply. It is 25 mph in business and residential districts and in school zones when children are present. It drops to 15 mph at blind intersections, in alleys, and within 100 feet of a railroad crossing where you can't see the tracks for 400 feet in both directions.
School zones
When you pass a school while children are outside or crossing the street, the limit is 25 mph — and may be posted as low as 15 mph directly next to the school. Slow down and watch for children and crossing guards, and obey any posted school-zone hours.
Adjust your speed for conditions
The posted limit is for ideal conditions. Slow down for rain, fog, snow, or ice, in heavy or merging traffic, on curves and hills, and near pedestrians or bicyclists. When you can't see far ahead — fog, a hill crest, or a sharp curve — drive slowly enough to stop within the distance you can see.
Speed limits on the California DMV test
The California knowledge test asks about the Basic Speed Law and the 25, 15, 55, and 65 mph limits — especially what applies when no sign is posted and how to adjust for conditions. Learn the numbers here, then practice with real DMV-style questions until they stick.
PassGolden is an independent service and is not affiliated with, endorsed by, or operated by the California DMV or any government agency.
Common questions
What is the maximum speed limit in California?
65 mph on most California highways, and 70 mph only where posted. On two-lane undivided highways it is 55 mph unless otherwise posted.
What is the speed limit in a residential or business area?
Unless a sign says otherwise, the prima facie limit is 25 mph in business and residential districts, and in school zones when children are present.
When is the speed limit 15 mph in California?
15 mph at blind intersections, in alleys, and within 100 feet of a railroad crossing where you cannot see the tracks for 400 feet in both directions.
What is the Basic Speed Law in California?
It means you may never drive faster than is safe for current conditions — even at or below the posted limit. In rain, fog, or heavy traffic, the safe speed is lower.