Where’s the data from?

Three sources, in descending order of weight:

1. ~200 store engagements I’ve done since 2017 — mostly Magento, but ~60 of those involved evaluating Shopify Plus, BigCommerce, SFCC, or WooCommerce as alternatives. The license / app / dev / hosting numbers come from invoices clients have shared during discovery, anonymised and median-aggregated by GMV bracket.
2. Public pricing pages + published case studies — Shopify Plus, BigCommerce Enterprise, Adobe Commerce, and SFCC all publish bracket-level pricing or have it leaked across enough vendor blogs to triangulate. The calculator’s license-tier brackets reflect those.
3. SI partner rate sheets — both my own ($65–$150/hr) and the Tier-1 SI rates I’ve seen quoted to clients (Magento OS: $50–$200/hr; Adobe Commerce: $150–$300/hr; SFCC: $250–$400/hr). These set the dev-cost upper bound.

What’s NOT in the data:

• Internal Adobe / Shopify / Salesforce pricing decks (I don’t have these and wouldn’t use them — vendor-supplied numbers are biased).
• Industry-report averages (Forrester / Gartner) — they bury variance and serve their sponsors.
• List prices for SFCC — SFCC pricing is opaque; I use the median of what clients have actually paid (~$200k/yr starter, scaling fast).

If you have invoice data and want to calibrate the model against your actual numbers, send it via the form — I’ll re-run.