Building a free US payroll calculator — what confuses you most about your paycheck?

Hey everyone! I've been building PayClear, a collection of free US paycheck, salary, and tax calculators (paycheck withholding, self-employment tax, bonus tax, state-specific calculators, etc.) — launching here on July 1st.

While building this, I realized how much confusion exists around simple things like:

- Why a bonus gets taxed differently than regular pay

- How self-employment tax actually works for freelancers

- Why take-home pay looks so different across states for the same salary

I'd love to hear: what's the most confusing thing about your paycheck or taxes that you wish a calculator could just explain clearly? Trying to make sure I'm covering the right gaps before launch.