Product documentation

Price Margin Checker: calculation scope and result interpretation

Executive summary

The Price Margin Checker estimates a first-pass gross margin from six inputs: sale price, product cost, shipping cost, platform fee percentage, fixed fee, and extra cost. It calculates platform fee, total cost, gross profit, and margin percentage, then labels the result workable, thin, loss, or missing.

The Tool does not supply current marketplace fees or taxes. You must obtain those inputs from the appropriate current source and use the same currency for every money field. The result is a preparation estimate, not tax, accounting, financial, or marketplace-fee advice.

Applicability

This documentation describes the current Dokuntag Publish web Tool as reviewed against repository package version 1.0.0 on 2026-07-20. Review it again whenever the Tool registry, calculation rules, service, result copy, or interface changes.

The Tool is available in English and Turkish:

The calculation runs in the browser and does not upload pricing data.

Before you begin

Choose one product, sales channel, currency, and calculation scope. Gather the sale price and every cost you intend to include, together with the source and effective date for any marketplace fee. Decide whether each amount includes or excludes tax before entering it; the Tool cannot make that distinction for you.

Inputs

Use one currency consistently. The interface's number display does not convert currencies.

Input	Meaning	Preparation check
Sale price	Revenue assumed for one sale.	Use the price for the same product, market, and tax scope as the costs.
Product cost	Cost of the product used in the estimate.	Use a documented cost basis appropriate to your review.
Shipping cost	Shipping amount included in this estimate.	State whether this is outbound shipping only or another defined scope.
Platform fee %	Percentage of sale price used to estimate the platform fee.	Verify the current rate for the relevant platform, category, account, and effective date.
Fixed fee	Fixed amount included per sale.	Confirm the currency and when the fee applies.
Extra cost / ads	Other cost amount included in this run.	Add only costs you intentionally want represented; record what the value contains.

Empty, negative, or non-numeric money values are treated as 0. The platform fee percentage is constrained to the range from 0 through 100.

Calculation method

The current rules use these formulas:

platform fee = sale price × (platform fee percentage / 100)

total cost = product cost
           + shipping cost
           + platform fee
           + fixed fee
           + extra cost

gross profit = sale price − total cost

margin percentage = gross profit / sale price × 100

When sale price is 0, margin percentage is 0 and the result is missing. The interface displays monetary results and the margin percentage with up to 2 decimal places, while the calculation uses the entered numeric values.

Result levels

Result	Current rule	Interpretation
missing	Sale price is `0` after input normalization.	Enter a sale price before reviewing margin.
loss	Gross profit is below `0`.	Included estimated costs exceed the sale price.
thin	Gross profit is not negative and margin is below 15%.	Small changes in costs may remove the estimated profit.
workable	Margin is at least 15%.	The first-pass estimate clears the Tool's current threshold; final costs and taxes still require separate review.

An additional platform-fee warning appears when the calculated platform fee is more than 22% of the sale price. This warning does not replace the main result level.

The 15% and 22% values are Tool thresholds, not universal marketplace targets or professional financial recommendations.

Step-by-step use

Choose one product, sales channel, currency, and calculation scope.
Record the source and effective date for each fee or cost outside the Tool.
Enter the sale price, product cost, and shipping cost.
Enter the verified platform fee percentage and any fixed fee.
Put other intentionally included costs in Extra cost / ads and record what they represent.
Review platform fee, total cost, gross profit, margin percentage, result level, and warnings together.
Repeat the calculation with plausible changes in shipping, returns, advertising, or other costs that matter to your decision.
Obtain qualified tax, accounting, or financial review when your decision requires it.

Reading the result safely

The output is only as complete as the inputs. A workable result does not show that every business cost was included, that a platform fee is current, or that a product will be profitable after returns, taxes, advertising, packaging, currency effects, or other omitted costs.

Use the result as a review prompt:

confirm the fee source and effective date;
verify that every money value uses the same currency;
identify costs still outside the calculation;
test how sensitive the result is to uncertain inputs;
keep the calculation record with its assumptions.

Common mistakes

Mixing currencies

The Tool does not perform currency conversion. A sale price in one currency and a cost in another produce a mathematically valid but economically unusable result.

Treating a percentage field as an official fee lookup

The Tool calculates from the percentage you enter. It does not retrieve a current platform rate or determine which rate applies to your account or category.

Leaving known costs outside the inputs

If an applicable cost is not represented in product cost, shipping cost, fixed fee, platform fee, or extra cost, it is not included in total cost.

Treating the threshold as advice

The thin and workable labels describe the Tool's fixed rules. They do not establish a suitable margin for your business.

Important limitations

No current fee table, tax rate, exchange rate, return rate, advertising rate, or category-specific charge is built into the calculation.
The Tool does not determine whether entered values include or exclude tax.
It does not model cash flow, payout timing, refunds, return probability, inventory loss, financing, or multi-period costs.
It does not replace marketplace settlement reconciliation or professional advice.
It does not guarantee profitability, pricing suitability, listing approval, or sales.
A later release may change inputs, formulas, thresholds, or result copy.

Troubleshooting

Problem	Check
Result shows missing	Enter a sale price greater than 0.
Platform fee seems wrong	Confirm the percentage input and calculate whether it applies to the same sale-price scope.
Total cost omits an expense	Add that scoped amount to an appropriate input; the Tool has no automatic external-cost lookup.
Result changes after replacing a comma with a period	Re-enter all fields and verify the parsed values shown in the result.
Tool behavior and this page differ	Stop using this page as current documentation and send both versions to Support for review.

Evidence and review

This page is based on the current Tool registry, deterministic calculation rules, service contract, and interface copy:

`tools.registry.ts`
`priceMarginRules.ts`
`priceMarginCheckerService.ts`
`PriceMarginCheckerClient.tsx`

Last reviewed: 2026-07-20

Required next review: Every release that changes the registry, rules, service, result copy, or interface; otherwise within 6 months.