Answer

My MacBook is overheating — is it dangerous?

Not immediately, but sustained heat shortens SSD and battery life. Check Activity Monitor first; if hardware, book a thermal repaste.

Software causes (Chrome tabs, Spotlight indexing, Time Machine) account for most MacBook overheating. If Activity Monitor shows nothing unusual and fans still spin loud, it's a hardware issue: dust-clogged vents or dried thermal paste. Intel MacBook Pro (2015–2019) especially benefits from repaste. HOPE Systems does complete MacBook thermal service in 3 hours.