A valid discount stack
can still lose money.
Stress-test one redacted cart before publishing a promotion. The model applies one product percentage first, two additive order percentages to the revised subtotal, and one shipping percentage last. It is deliberately narrower than Shopify checkout and must be reconciled there.
Limited discount-stack contribution model
| Line | Qty | Unit price / cost | Extended price / cost | Product discount | Cost source | Estimated |
|---|
This is a limited, dated scenario—not Shopify checkout, an order prediction, accounting gross/net profit, tax, refund, inventory valuation or permission to publish. Test the exact cart in the current authorized checkout.
Commerce boundary: inputs remain in this browser; the paid report receives only redacted aliases, user-entered amounts, rule counts and source references. No storefront, checkout, orders, customers, suppliers, payment processor or accounting system is connected. The model excludes fixed-amount discounts, Buy X Get Y, eligibility segments, subscriptions, selling plans, Markets, taxes, multiple delivery groups, custom Functions and same-line multiple product discounts. Shopify and installed apps remain authoritative; an authorized merchant must test and approve the exact promotion.
$5/mo Promotion margin review membership
Unlock repeat editable Markdown reviews for up to 50 cart lines, with step-by-step discount arithmetic, no-promotion comparison, cost stack, dated rule holds and merchant/finance signoff. Re-run when a promotion, cost or Shopify rule changes.
- integer-cent limited stack arithmetic
- no-promotion contribution comparison
- rule-count and source-freshness holds
- line cost and estimate register
- merchant and finance checkout signoff
Current Shopify rules and the deliberately narrow first release
先核对当前来源与工具边界Check current sources and tool limits first