Do protons weigh the same as neutrons?

YES AND NO

When using Relative Atomic Mass (Mr), a proton weighs the same as a neutron.

This is rounded to the nearest whole number, however.

The actual weight of a proton is 1.0073 amu.

The actual weight of a neutron is 1.0087 amu.

As you can see the neutron actually has slightly more mass (weight) than a proton has.

When using figures to calculate Mr, however, as in most periodic tables, the mass of protons and neutrons is both 1.