This has been posted many times before, and AFAICT it’s fundamentally misleading, as it doesn’t account for transfer payments (refundable tax credits, food stamps, housing vouchers, ACA subsidies, …)
That artificially inflates the “wage level” needed for the estimated living standard. It also makes the tax figures absurd. No two-parent, two-kid household making $110K is paying 15% of that net in taxes, subtracting deductions, credits and subsidies.
IOW, our “safety net” for middle-income parents could get 5X more generous and this calculator would show the same results.