How old is he/she? Looks like a pullet to me. Dark coloring, not silvery like a cockerel. Do the front of the legs have a dark wash of color down the front? If so, probably you have a pullet.
How am I ever going to get as smart as all of you are? Everybody has a trick on telling the boys from the girls. I'm so clueless! I'll never learn all his stuff.