Stop running out. Stop over-ordering.

The Problem

Inventory decisions are the highest-leverage operational choice you make. They're also the most error-prone.

A stockout on a top-10 SKU doesn't just cost you that day's sales. It costs you Buy Box position while you're out, organic rank recovery time after you're back in stock, and review velocity you'll never recapture. For a seller doing $100K/month on a single ASIN, a 4-day stockout is a $13K loss — plus weeks of ranking damage.

Over-ordering is just as bad, slower. Dead stock costs you storage fees, LTSF charges, and capital you can't redeploy. The standard approach: a spreadsheet with 90-day velocity, a guess at lead time, and hope. The result: you stockout on 3 SKUs while sitting on 120 units of something that sold 4 times last quarter.

The tools most sellers use don't connect inventory to sales velocity, to Buy Box ownership, to ad spend, or to purchase order history. They're snapshots, not systems.

How It Works

Seller Calculus pulls live FBA inventory, warehouse stock, inbound shipments, and open POs into a single model. Every SKU gets a days-of-supply calculation based on actual 30/60/90-day velocity, not guesses. When days of supply drops below your configured threshold, a reorder recommendation surfaces automatically.

The Fragility Score flags SKUs that look fine on the surface but are at risk: high velocity, thin inbound buffer, long vendor lead time, seasonal demand curve approaching. A fragility score of 80+ means the SKU can absorb demand variance. A score of 30 means you have 12 days before a stockout, not the 45 your inventory count implies.

The PO Builder takes reorder recommendations and turns them into purchase orders with vendor, quantity, and margin waterfall pre-calculated. Your purchasing team approves, not builds from scratch.