Upvote:1
Traveling from Orange County up to San Francisco can take anywhere from 4-8 hours, heavily depending on traffic around LA. If you plan on leaving by 0430 and take I5, you'll most likely be pushing it just to make it by noon the same day. Of course this is also dependent on where in Orange (North or South) you are, and where in SF you wish to get.
Upvote:2
There are 3 main routes you can take between the Los Angeles region and San Francisco - Interstate 5, US Highway 101, and State Route 1.
Interstate 5 is the major commercial route between LA and San Francisco (and continuing on to the Mexico and Canadian borders). It runs inland, and is a relatively straight, high speed (70 MPH) road, that is about as boring as any other interstate you'll come across. It is the fastest route, and depending on the day of the week, the time of day, and the traffic will likely take somewhere between about 5 1/2 and 8 hours from Orange County to San Francisco.
US Highway 101 takes a more coastal route before heading inland and continuing up to the San Francisco Bay area, along the bay, and into San Francisco. It is a slightly more scenic route - especially along the first part of the route where it runs near to the Pacific coast. However it is longer than Interstate 5, and generally slower (65MPH, slower in many parts) - likely taking at least about an hour longer than Interstate 5.
State Route 1, often known as the Pacific Coast Highway (PCH) is the ultimate scenic route - it travels the majority of the way along the Pacific Coast as the name implies, giving stunning views over the ocean. Much of the route is twisty, and speed limits along much of it are around 35MPH so it is significantly slower. There are also numerous sights and photo opportunities that will normally extent the trip even further. Depending on conditions, it will likely take somewhere between 9 and 12 hours to take this option.
Given the time constraints you have, the PCH is not going to be an option, so you can pretty much choose between the quick, easy and boring route of Highway 5, or the longer, slower, but slightly more scenic route of Highway 101.
Personally I'd recommend trying to find some additional time, and doing the PCH - preferably split over 2 days, but even doing it in 1 day is far more enjoyable than highway 5/101.