How does this account for inflation / pricing changes?

It doesn’t — deliberately. The 3-year horizon uses 2026 nominal pricing without inflation adjustment, for three reasons:

1. License + hosting tend to step rather than smooth. Adobe doesn’t raise prices 3% a year — they hold flat for 18 months and then add a tier or rebrand. Modelling smooth inflation creates false precision.
2. Per-tx fees and apps scale with GMV, not inflation. The calculator has a growth multiplier (flat / 1.5x / 3x / 5x+) that adjusts these. If you also want 3% annual inflation on top, multiply the total by ~1.09 over 3 years.
3. Dev rates are sticky. The freelance rate I quote a $5M client today is not 3% higher than 2 years ago — it’s either the same, or 20% higher because skills compounded. Smooth inflation doesn’t model how labour markets work.

If your finance team wants a CFO-grade NPV, the procedure is:

• Take the calculator’s 3-year total
• Discount Year-2 by ~5%, Year-3 by ~10% (use your weighted-average cost of capital)
• Add a 5–10% contingency for vendor price increases
• Add 10–20% contingency for scope creep

For a Year-1 vs Year-2 vs Year-3 split (rather than a flat total), the rough breakdown for each platform is in the calculator code — let me know via the form and I’ll send the year-by-year.