Free calculator
Inventory shrink calculator for c-stores and gas stations.
Enter your weekly category sales (tobacco, beverages, snacks, general merchandise) and an estimated shrink rate per category. See dollar exposure per week, per month, per year, with industry-benchmark context.
Category sales and shrink rates
Tobacco
Beverages
Snacks
General merch.
Exposure
Industry average
Aligned with the NACS c-store industry average of 1.5–2.5%. Typical for independents without serial-level lottery or SKU-level invoice OCR.
Industry benchmarks: NACS State of the Industry reports + StationPro pilot data. Weighted rate = total shrink / total sales.
How this is computed.
Category-level weekly sales.
Tobacco, beverages, snacks, general merchandise. Pull from POS category reports.
Per-category shrink rate.
Tobacco: typically 2–4%. Beverages: <1%. Snacks: 1–2%. General merchandise: 1–3%.
Weekly shrink per category.
Category sales × category shrink rate.
Weighted total shrink.
Sum of category shrinks. The single number to track week-over-week.
Annualized exposure.
Weekly total × 52.
Industry benchmark comparison.
NACS reports 1.5–2.5% as the c-store industry average. Your weighted shrink rate (total shrink / total sales) maps against that range.
What the result tells you.
A 2% weighted shrink on $30,000/week category sales = $600/week = $31,200/year. Cutting from 2% to 1% (typical move with serial-level lottery, SKU-level invoice OCR, and rolling cycle counts) recovers $15,600/year per store. Multi-store operators multiply.
Use this when…
- Sizing your shrink problem by category.
- Identifying which category to focus on first.
- Building the ROI case for inventory tracking software.
- Comparing portfolio shrink across stores.
Related.
Features
Buyer guides
Convenience store back office software for independent operators.
Tobacco shrink, lottery accountability, vendor invoice automation, manager closeout, and multi-location reporting in one workspace, built for c-store density, not enterprise ERP.
Inventory shrink software for c-stores and gas stations.
SKU-level invoice ingestion, vendor cost change flagging, mobile cycle counts, and shift-level shrink attribution, built for the c-store SKU density (tobacco, beverages, snacks, candy) that breaks generic retail tools.
From the blog
The lottery shrinkage playbook.
How to instrument scratcher accountability across barcode scanning, serial-gap detection, and shift attribution. The four-week sprint that closes the leak.
Invoice OCR vs. manual entry, in dollars.
A working calculation for the labor savings, error reduction, and price-leak capture when you stop typing vendor invoices and start scanning them.
FAQs.
How accurate are these shrink rates?
Directionally accurate, based on NACS industry reports and pilot data from independent c-stores. Your actual rates depend on staff training, neighborhood density, POS workflow, and a few other factors. Use the calculator to estimate ranges, not point estimates.
Does tobacco include vapor / e-cigs?
Yes, for this calculator. Vapor SKUs shrink at similar rates to cigarettes (pocketable, high-value). Track them as a tobacco sub-category in your POS if you want finer granularity.
Should I include lottery in inventory shrink?
No, lottery is tracked separately (see the lottery shrink calculator). Lottery has a different shrink mechanic (serial-level, state-commission-reconciled) and shouldn't be aggregated with general merchandise.
See how StationPro automates inventory shrink calculator.
A 30-minute demo. We walk through the underlying workflow in your station's actual data.