The margin formula FT009 uses
The calculator starts with sell price, then subtracts product cost, handling cost, box cost, and estimated shipping. The remaining dollars are estimated gross margin before marketplace fees, taxes, refunds, or advertising costs.
Why box cost belongs in the calculation
Small sellers often compare shipping labels but forget the box itself. A stronger box may prevent damage, but it can also be heavier, larger, and more expensive. A cheaper mailer may reduce cost, but only if it protects the item and avoids customer damage claims.
What to look for in the result table
Negative margin
The sale may lose money before fees. Change price, packaging, or product economics before shipping.
Below target
The shipment may still be profitable, but it does not hit your target gross margin.
Best margin
The best viable box among the options you entered, not a guarantee that the shipment is priced well overall.
How to use this before listing
- Enter your planned sell price and product cost.
- Add realistic handling cost for packing labor, filler, tape, label, or inserts.
- Enter the box cost for each candidate package.
- Compare margin status across boxes.
- Use the target sell price column to decide whether the listing price needs to rise.
What this does not include
The margin estimate does not include marketplace referral fees, payment processing, ad spend, returns, replacement shipments, insurance, taxes, customs, or final carrier surcharges. Treat it as a packaging and price planning layer before your final shipping software check.