Why paper cuts hurt?
The main reason why paper cuts are so painful primarily lies in the fact that you usually get them on your fingers, particularly your fingertips. Fingertips and hands have significantly more nociceptors (nerve fibres) per square millimeter than most of the rest of your body, such as your legs, arms stomach area etc. This ends up making cuts on your fingertips feel significantly more painful than cuts elsewhere, even when they are produced by paper or similar objects.
But why do paper cuts seem to hurt more than other types of cuts on the hand? This is thought to be because the edges of paper are very dull and flexible, compared to knives and other such sharp objects. Because of this, when paper cuts your flesh, it does a lot more microscopic damage as it rips through your skin. Not only is there more microscopic damage, but this damage is also very shallow on the skin. This will further increase the pain because some of the most sensitive nerves in your skin, which have very low thresholds to trigger, are near the surface. They also tend to hurt longer because they won't bleed much and sometimes not at all. This leaves the nerves open to the air other irritants, so they will continue to be in an activated state for much longer than more significant cuts.
