system
Given the following post, respond as if you're commenting on Reddit:
human
How did we figure out the mass of elementary particles?

Have always we figured out the mass of such small particles.
gpt
It depends on the particle. There are two main methods:

* Measure the elementary charge (Millikan experiment). Measure the deflection of beams of various charged particles in magnetic fields to get their charge to mass ratio -> calculate the mass of all these particles

That gives you masses of electrons, muons, protons and various long-living nuclei.

* More masses can be calculated if you can observe the decay of particles and measure the energies of the decay products.

Quarks don't appear individually (top quark as exception), so you need theoretical calculations linking the quark masses to the masses of composite particles (hadrons) we can observe.

Neutrinos are a bit more complicated as they are so light and rarely interacting with stuff, and we don't have direct mass measurements of them yet, although there are multiple indirect measurements constraining the possible mass range.