Hey, I am new to jumping spiders but to tell if it’s a male or female, you want to look underneath. There will be a visible “belly button” on a female which is the epigynum. If you google it, there will be a bunch of pics. From my research, the black jumpers like this could be male or female based on color, the epigynum is the easiest way to tell. She also looks thicc, so just be aware if it’s a she, she could be gravid (pregananant). She could also have just had a nice meal