Is it normal to fantasize about a coworker?
Mostly.Normal for most people
Yes, it’s normal to fantasize about a coworker now and then. A fantasy doesn’t mean you need to act on it; keeping things respectful and professional at work is what matters.
Work puts you around the same people a lot, so a spark—or an unexpected daydream—can happen. Plenty of people have fantasies they never intend to turn into anything, and it doesn’t automatically mean you’re unhappy in a relationship or planning to make a move.
You can let the thought pass without making it a big deal. If you do have real interest, think carefully about workplace boundaries, power differences, and whether pursuing it could make things uncomfortable for either of you. And if they’re not interested, keep it professional.