Noticing tiny red spots on your skin can be unsettling, especially when they seem to appear out of nowhere. Sometimes they develop gradually, while in other cases they can show up quite suddenly. The good news is that many causes of small red spots are harmless, but some may be linked to underlying health conditions and deserve medical attention.

One common explanation is cherry angiomas, small bright-red spots or bumps formed from tiny blood vessels. They are generally harmless and become more common with age. Another possibility is petechiae—tiny red, purple, or brownish spots caused by bleeding beneath the skin. Unlike many rashes, petechiae typically do not fade when pressed. Skin irritation, eczema, or contact dermatitis can also cause redness, itching, and dryness. But these aren’t the only possibilities—several other common conditions can produce tiny red marks that look surprisingly similar.