Resources

Free tools for founders who want to know their numbers.

Practical tools and plain-English maps of your numbers - built for consumer brand founders who are serious about profitability.

Free · available now

The Money Map

See exactly where your Amazon money went last month - what you kept, and what Amazon took, in plain English. Runs inside the AI you already use, on your own report.

Open the Money Map →
Free · available now

The Amazon Payout Status Map

See the payout transfers Amazon recorded this period and how much is still marked Deferred - a clear status snapshot, not a guess about your bank. Runs inside the AI you already use, on your own report.

Open the Payout Status Map →
Free · available now

The Inventory Map

See how many units you're holding in Amazon's warehouses and what it costs you every month to store them - including the aging surcharge on stock that's sat too long. Runs inside the AI you already use, on your own report.

Open the Inventory Map →
Free · available now

Amazon FBA Unit Economics

See what it costs to sell one unit on Amazon - in a regular month and at holiday peak rates. Referral, FBA fulfillment, storage, placement, 3PL, ads and returns, from Amazon's own published 2026 rate cards.

Open the calculator →
Free · available now

Shopify Fee Calculator

See what each Shopify plan really costs you in fees, and which one costs the least at your revenue. Plan cost, processing rate, and per-transaction fees, all in one number.

Open the calculator →

New tools ship regularly. They land here first.

Stay in the loop

Want to hear when new tools drop?

Get new tools and plain-English finance tips as they land. Unsubscribe any time.

We'll only use your email to send you new tools and the occasional note - unsubscribe any time. See the Privacy Policy.

Daily content

Follow along on Instagram.

Daily posts breaking down Amazon fees, ecommerce margin concepts, and financial strategy for founders - in plain English.

@marginsandme →