It's in the oven right now
since cooking heat and thickness of fish vary, i many times find it the best to use an instant read thermometer to test, especially as fish is so expensive nowadays. if you let it go too long, it loses its moisture and you can tell by the fish sitting in a bunch of liquid. i also tend to put my fish in a simple marinade (usually soy, ginger, sesame, honey, grated onion) outside of the fridge until i think it becomes room temp so it cooks to the center without outside being dry.
I know this is late, but for future reference when baking go for about 425F 10 minutes per inch.
There's a ten minute per inch thing, but for me, that's too well done. If fish is flaky, it's overdone. I like doing salmon on the stovetop so I can watch the opaqueness (made up word) travel up the fish. One third up..flip..next one third up, take it out of the pan. It continues to cook to the point that the middle is medium rare which is how I prefer it. Hopefully your salmon turned out perfectly. We need a little more notice to help you. :)