"Can someone explain the math used to suggest that $325,000 is the same as $100K in the 1990s? Because the math ain't mathin." — It maths, actually. Both sides. It depends entirely on which prices you measure against. Set a year and an amount, then flip between the official CPI basket and a housing/college/healthcare-heavy basket.
The Consumer Price Index (CPI-U) tracks a fixed-ish basket of everything urban consumers buy: food, rent, gas, clothes, electronics, services. The conversion is one division: equivalent = amount × (CPI now ÷ CPI then). By that math, $100K in 1995 ≈ $214K in 2026, and $100K in 1990 ≈ $249K. So the "$325K" claim overshoots the official number by 25–50% — the CPI math genuinely doesn't produce it.
CPI averages everything — including TVs and software that got dramatically cheaper. But the big life-purchases outran it: the median US home roughly tripled-plus since the mid-90s, published college tuition roughly quadrupled, and medical costs grew well above CPI. If your personal basket is dominated by a mortgage, tuition and insurance premiums — as it is for many mid-career families — your true inflation rate was higher than CPI. Weight the basket that way and $100K-in-1995 lands around $290–330K today. So: "$214K" and "$325K" are both defensible answers to different questions. The math maths — the baskets differ.