Ecommerce Order Profitability Planner methodology

R = Pₙ ÷ (1 + g)

T = Pₙ − R

F = Pₙ × f + F₀

E = max(0, q × (R + L − Cᵣ − Fᵣ))

K = R − C − F − A − E

m = K ÷ R

Bᵣ = R − C − F − E; B = { Bᵣ, Bᵣ ≥ 0; ∅, Bᵣ < 0 }

Money inputs and outputs use the currency selected in the scenario without changing the canonical methodology. Rates, margins, utilisation and buffers are entered as percentages and converted to decimal values for calculation.

• All variable-cost components should reconcile to revenue less contribution.
• Customer price must reconcile as ex-indirect-tax revenue plus the tax amount removed.
• Increasing any single cost by 1 currency units reduces contribution by 1 currency units when other inputs stay fixed.
• A zero provider fee rate and zero fixed fee produce no provider fee. Better product recoverability or fee reversal cannot reduce contribution.
• A raw advertising ceiling of exactly zero is a reachable zero break-even; a negative raw ceiling is unavailable because the order loses money before advertising.

• Product, fulfilment, packaging, advertising and reverse-logistics amounts are user-entered ex-indirect tax economic costs. Confirm their accounting treatment against your records.
• Percentage provider fees are applied to the customer price including indirect tax; the fixed fee is the user-entered provider contract amount. The planner does not infer indirect tax credits or provider tax treatment.
• The indirect tax rate is an editable user assumption used to distinguish tax-inclusive and tax-exclusive amounts where selected; confirm the applicable jurisdictional treatment.
• Contribution and contribution margin are calculated planning outputs; they are not net profit or an accounting classification.

This planner has no current policy-data dependency. Its commercial assumptions are user supplied. Registered family-level regression suites exercise the shared business-logic engine and worked-result reconciliation.

• The model excludes fixed overhead, wages not entered as per-order costs, inventory timing, income tax and working-capital effects.
• Provider and marketplace fees can have tiers, caps, categories and contract-specific tax treatment. The planner does not claim a current provider preset.

This is educational decision support, not tax, accounting, legal or financial advice. Check the treatment of your actual transactions under the rules that apply to your business and seek qualified advice where appropriate.

Registered family-level suites test formula invariants and example reconciliation; the release ledger records that coverage without claiming a separate oracle for every line of public copy. There is no official threshold or benchmark to refresh for this planner. Commercial inputs remain user-supplied because they vary by business and contract.

1. 2026-07-31: Initial public release of the planner and methodology after pre-launch calculation, content, source and interaction review.