How this is calculated
Profit = revenue - materials - fees - other costs - the mileage deduction (miles x the IRS rate, which also approximates your real vehicle cost). Then both taxes hit: self-employment tax at 15.3% of 92.35% of profit - the tax W-2 people never see because employers pay half - and income tax at your marginal rate, because side income stacks on top of your salary, not beside it.
real wage = (profit - SE tax - income tax) / all hours
The two lies side-hustle math usually tells
Counting only "making" hours - photography, listings, customer messages, packaging and the post-office run are hours too. And using average instead of marginal tax - your thousandth side-hustle dollar is taxed like your last salary dollar, not your first. Fix both and many hustles pay under minimum wage; the good ones prove themselves.
Notes
Half the SE tax is deductible against income tax (included). Hobby-loss rules, inventory accounting and state tax are not modeled. If profit clears about $1,000/yr, remember quarterly estimated taxes.