// Tools

Free retail planning calculators

Vendor-neutral retail math, free and no sign-up — open-to-buy, sell-through, GMROI, and lead-time / on-time-delivery. Each shows the formula and how to use it.

Open-to-Buy (OTB) Calculator →

Retail dollars you can still receive this period — and whether you are overbought.

Sell-Through Rate Calculator →

The share of received units that have sold — reorder or markdown signal.

GMROI Calculator →

Gross-margin dollars earned per dollar of inventory at cost.

WSSI Calculator →

Weekly Sales, Stock & Intake — project closing stock and weeks of cover.

Lead-Time / On-Time-Delivery Calculator →

Project an order’s arrival against the in-store date and see the slip risk.

These do the math one figure at a time. RetailNorthstar runs it across every style, channel, and season — connected to one plan.

Book a Demo →