Ecommerce Gross Margin Calculator accuracy and testing

Formula source

• Gross profit = revenue - COGS - variable fees - shipping subsidy. Gross margin percent = gross profit / revenue x 100.

Test cases

Known limitations

• These calculators do not fetch live carrier rates, marketplace fees, duty schedules, ad platform data, exchange rates, tax rates, or fulfillment provider pricing. Enter the current assumptions that apply to your store.

Assumptions

• All prices, costs, rates, duties, shipping charges, and campaign assumptions are user-entered.
• Calculations are deterministic and run locally in the browser without uploading ecommerce or customer data.
• Results are planning estimates and do not include every tax, refund, chargeback, inventory, financing, or accounting adjustment.

Unit handling

• Revenue accepts values in $.
• COGS accepts values in $.
• Variable Fees accepts values in $.
• Shipping Subsidy accepts values in $.
• Gross Margin is displayed as a percentage.
• Gross Profit is displayed as currency.
• Total Variable Cost is displayed as currency.
• Variable Cost Rate is displayed as a percentage.

Rounding rules

• Number displays use up to 2 decimal places in the calculator UI.
• Currency outputs are displayed with standard US dollar formatting.
• Percent outputs are displayed with two decimal places.
• Input precision follows configured step values where provided.

Version history

Change log