I am a first-timer. Will I be the slowest person out there, and will anyone care?
Only 2 of the 26 races here have published finish-time results, so there is not enough local data to give you a meaningful picture of what the field looks like. What does help: several races here also offer a 1 Mile option alongside the 5K, so if you want to ease in even shorter, that choice exists at many of these events.
What is this going to cost me, and does waiting to register make it more expensive?
Entry fees run from $25 to $50, with a typical fee of $30. One race already has a price increase scheduled, so if you see a race you want, registering early is the safer move for that one.
Am I going to get a shirt?
23 of the 26 races say they give a shirt. The other 3 have not published any giveaway details - which means they have not said no, just nothing at all.
When are most of these races? I need one that fits my training block.
Fall, from September through November, is the busiest stretch with 10 races. Winter, from December through February, brings 8. Summer, June through August, has 7. Spring is the quietest window - only 1 race runs from March through May, and the quietest single month is March with just 1 race.
Do these races also offer longer distances if I want to step up from the 5K?
Most do. Of the 26 races here, 24 also offer a 10K and 23 include a Half Marathon - so if you use a 5K as a starting point and want to go longer at a future edition of the same event, most of these races have that option waiting for you.
Are there trail 5K races near San Francisco?
Yes, one race around San Francisco gets you off the pavement: 1 mixes road and trail. Surfaces are not always published, so it is worth checking a specific race before you register.