每一層級，逐項列明

基本稅率、第301條、第232條疊加、排除項目、各項費用：單一到岸成本數字，並列出每一筆明細。絕無來路不明的總額。

Modern US tariffs stack: a base rate, a Section 301 list, a country-wide floor, a Section 232 metal action that chains through autos into steel and aluminum, a fee schedule on top. Tariff Monster resolves the whole stack for your HTS line, origin, and entry date, and shows its work — every charging heading appears as its own line with its own 9903 citation, rate, and dollar amount, down through the Merchandise Processing Fee and harbor maintenance to a single landed cost.

Exclusions are first-class, not fine print. When a heading you could claim exists — an informational-materials exemption, a deal carve-out, a content-based exclusion — it surfaces as a toggle on the quote. Claim it and the affected layer is replaced, the total recomputes, and the breakdown shows exactly which line the claim suppressed. Where an action needs facts only you have (metal content value, melt-and-pour origin), the simulator asks for them instead of guessing.