paycheck

A salary is a gross number; what you can budget is what's left after taxes. This lesson separates gross from take-home, breaks a paycheck into federal income tax, Social Security, and Medicare, and clears up the single most common tax misconception — that your top bracket is the rate you pay on everything. Drag a salary and watch the split.

Most workers never choose how much income tax leaves their paycheck — a W-4 they filled out on day one quietly decides it, and the result shows up once a year as a refund or a bill. This lesson reframes the refund everyone celebrates: a refund means you overpaid your taxes all year, and the government is simply handing your own money back, interest-free. The amount your employer withholds is set by your W-4; it has nothing to do with the tax you actually owe, which is fixed by your income. If withholding exceeds the tax, the excess comes back as a refund; if it falls short, you owe a bill in April (and risk an underpayment penalty if you cut it too close). The simulator makes the timing visible: it plots the running pile of over-withheld tax climbing through the year and sitting with the IRS until spring — the size of the interest-free loan — and prices the interest that money could have earned if it had stayed in your paychecks. The 'aha' is that a $2,800 refund is exactly the ~$110 you handed over every payday and could have kept, invested, or used to pay down debt. The durable lessons: the tax you owe doesn't change with withholding, only the timing does; a refund is a sign you mis-set your W-4, not a prize; the target is a refund near zero; and under-withholding has its own trap — a surprise bill plus a possible penalty. Dialing in your W-4 is one of the highest-leverage, lowest-effort money moves there is.