How to Check Shopify Discount Prices & Gross Margins

Calculate the price after a percentage discount

Start with the current selling price, product cost and the discount rate for the selected variant. Keep the inputs in the store’s base currency. For a simple supported percentage discount, the calculation is:

Discounted price = selling price × (1 − discount rate)

Estimated gross margin = (discounted price − product cost) ÷ discounted price × 100

If the discounted price is zero or the cost is unavailable, do not report a normal margin percentage. Resolve the inputs first. This estimate is not net profit: taxes, shipping, payment fees and other business costs need a separate assessment.

Worked example: $100 price, $70 cost, 20% discount

These are illustrative inputs, not results from a merchant or a real campaign.

Input or result	Example
Current selling price	$100
Product cost	$70
Discount	20%
Calculated discounted price	$80
Estimated gross margin	12.5%
Example minimum price rule	$85 — below the chosen limit
Example minimum margin rule	20% — below the chosen limit

The product has $10 left between the discounted selling price and its recorded product cost. Dividing that $10 by the $80 discounted selling price gives a 12.5% estimated gross margin. It is not 30%, which would describe the margin before this discount.

The thresholds are your team’s choices. This example does not recommend a universal price floor or margin target.

Check missing costs and the discount’s actual scope

A blank cost must stay visible. Treating it as zero produces an optimistic margin that has not been supported by data. Review the cost for each relevant variant, not just one example product.

Also check which products and buyers the discount applies to, its dates and whether other discounts can combine with it. Shopify’s discount combination documentation explains why checkout behavior needs its own review. A simple calculation cannot represent every combination, customer condition or checkout outcome.

Choose a spreadsheet or a recurring check

A spreadsheet can work for a small, one-off promotion with clear inputs. Keep a copy of the scope, calculation and thresholds you approved. If prices, costs or discounts change during the campaign, repeat the calculation using the changed inputs.

PromoFinch brings defined price floors, estimated gross-margin limits and maximum discounts together for a supported subset of basic Shopify percentage discount codes and automatic product percentage discounts. It reports findings with the inputs behind each calculation. Missing costs and unsupported conditions remain visible.

Know what PromoFinch can check

PromoFinch uses the store’s base currency and available product costs. Uncertain discount conditions remain unsupported. Basic discounts with active or scheduled Shopify Rollouts are outside the supported check. Do not approve a campaign just because the supported part looks acceptable: review the report’s coverage and unresolved inputs too.

The app is read-only. It does not block a checkout discount, change prices, automatically restore prices or simulate a full checkout. It does not calculate net profit or certify legal price compliance.

Monitor the campaign and its ending

After reviewing a complete supported check, you can approve starting values as a campaign baseline in PromoFinch. During the sale, review new findings when a price, cost or discount changes. Afterward, compare selling and compare-at prices against the approved starting values, and investigate differences in Shopify.

A compare-at value, a current selling price and a percentage discount are separate inputs. Do not assume that every crossed-out price implies the same discount calculation.

A campaign review checklist

1. Select the campaign’s products and variants.
2. Confirm usable product costs and the base currency.
3. Record minimum price, minimum estimated gross margin and maximum discount rules.
4. Review unsupported discounts and missing inputs.
5. Calculate supported scenarios and resolve findings before approving the baseline.
6. Review changes during the sale and compare prices when it ends.

See PromoFinch’s supported discount checks and installation link.