At first, the hairy body of this butterfly threw me and I wondered if it was a type of moth. Some of them too have colorful wings. But I did find the identity, and it is a butterfly.
I learned some interesting information on Wikipedia https://en.wikipedia.org/wiki/Lorquin's_admiral), "Lorquin's admiral (Limenitis lorquini) is a butterfly in the Nymphalinae subfamily. The butterfly is named after Pierre Joseph Michel Lorquin, a French naturalist who came to California from France during the Gold Rush, and made important discoveries on the natural history of the terrain." Who would have known?
About the description, the website says, "The Lorquin's admiral has brown-black wings, each with a row of white spots across it. Its forewings have orange tips. Wingspan: 47 to 71 mm; females are generally larger than males."