Amazon FBA Unit Economics — Profit, ROI and Break-Even per Unit

Unit economics from your own quote
Takes your supplier cost, freight per unit, sell price, referral percentage, fulfilment fee, storage, ad spend and return rate and returns net profit per unit, margin, ROI, total Amazon fees per unit and total cost per unit. Nothing is pre-decided for you: every figure in the sum is a field you type.

FBA or FBM fee model
One selector changes which fee model the arithmetic uses. On FBA the fulfilment fee and the monthly per-unit storage charge are both applied; on FBM the same fulfilment field becomes your own pick-pack-ship cost and Amazon storage is set to zero. The same product can be scored both ways in two clicks.

Break-even sell price
Solves for the sell price at which net profit is exactly zero, taking into account that the referral fee and the ad spend both scale with the price you charge. This is the number to compare against the listings already on the search page before you order.

Monthly net and cash tied up
Multiplies the per-unit result by your expected units per month to show monthly net profit, and shows the landed cash (unit cost plus freight) you must have out at that rate — the figure that decides whether you can actually fund the order.

Remembers what you last typed
The popup stores the last set of values you entered and restores them the next time you open it, so screening the next supplier quote means changing one or two fields, not re-typing ten. This is the only reason the extension asks for the storage permission; it makes no network request and sends nothing anywhere.

Offline install, no account
Runs with no login, no internet connection and no data leaving your browser. To install: open chrome://extensions in the address bar, turn on Developer mode (top right), then click Load unpacked and select this folder. This is a direct-install build rather than a Web Store listing, which is why Developer mode is required; Edge and Brave install it the same three ways. Menu wording differs between Chrome versions and interface languages, so look for the nearest equivalent.