How do you calculate a stockout risk score?

Multiply the severity score by the occurrence score by the detection score, exactly like an FMEA risk priority number. The three ratings capture how damaging a stockout would be, how frequently it is likely to occur, and how hard it is to detect before it bites.

What do severity, occurrence, and detection mean for stockouts?

Severity is the operational and revenue impact if the item runs out. Occurrence is how likely a stockout is given demand variability and supply reliability. Detection is how well your systems and signals would warn you in time to react — a low detection score means the stockout would blindside you.

What is a good stockout risk score?

Lower is better. There is no universal threshold because it depends on your scale, but items clustering at the high end of the range should get action first. Rank the whole population and treat the score as a relative priority, not a pass/fail line.

How is stockout RPN different from a standard FMEA?

The math is identical — severity times occurrence times detection — but the failure mode is specifically 'this SKU or component goes to zero on hand.' It reframes classic reliability FMEA thinking for demand and supply planning rather than for a product or process failure.

Should I use the same scale for every item?

Yes. The score is only comparable if every SKU is rated on the same defined scale for all three factors. Write down anchored definitions for each level before scoring so two planners rate the same situation the same way.

What should I do with a high detection score?

A high detection score means a looming stockout would go unnoticed until it's too late — so the highest-leverage fix is often better visibility (min-max alerts, supplier ASNs, consumption tracking) rather than simply adding stock.

S&OP, Demand Planning & Forecasting calculator

Stockout Risk Calculator

Stockout risk scoring adapts the FMEA risk priority number (RPN) method to inventory, turning three judgment calls — how bad a stockout would be, how likely it is, and how well you'd see it coming — into a single comparable number. Demand planners and supply chain risk managers use it to triage which SKUs or components deserve safety stock, dual sourcing, or tighter monitoring, without treating every part as equally critical. It matters because stockout consequences are wildly uneven: running out of a $2 fastener that idles a $2M line is a very different risk than running out of a slow-selling accessory. A structured score forces those conversations to be consistent instead of driven by whoever complained loudest last week.

What this calculator does

Estimate stockout risk for sandop, demand planning and forecasting using production-ready inputs so teams can rank risks and decide which issue needs containment, controls, or escalation first.
Use it when stockout risk in s and op, demand planning and forecasting needs a defensible ranking against other s and op, demand planning and forecasting risks for the next review.
It multiplies severity, occurrence, and detection scores into a single stockout risk priority number so items can be ranked on a common scale.

Formula used

Stockout risk score = stockout risk severity score × stockout risk occurrence score × stockout risk detection score
Use the same scoring scale across comparable stockout risk risks.

Inputs explained

Stockout Severity (impact if it happens):
Stockout Occurrence (how likely):
Stockout Detection (how visible beforehand):

How to use the result

Use it when triaging a catalog of parts or SKUs for safety-stock investment, supplier redundancy, or heightened monitoring during an S&OP risk review.
The score is only as good as the rating scale behind it; ordinal 1-10 scores are not truly multiplicative, so use the number to rank and compare, never as an absolute probability of stockout.

Current U.S. benchmarks

The producer price index for steel mill products stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 3,569 primary metal manufacturing establishments employing about 354,911 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate a stockout risk score? Multiply the severity score by the occurrence score by the detection score, exactly like an FMEA risk priority number. The three ratings capture how damaging a stockout would be, how frequently it is likely to occur, and how hard it is to detect before it bites.
What do severity, occurrence, and detection mean for stockouts? Severity is the operational and revenue impact if the item runs out. Occurrence is how likely a stockout is given demand variability and supply reliability. Detection is how well your systems and signals would warn you in time to react — a low detection score means the stockout would blindside you.
What is a good stockout risk score? Lower is better. There is no universal threshold because it depends on your scale, but items clustering at the high end of the range should get action first. Rank the whole population and treat the score as a relative priority, not a pass/fail line.
How is stockout RPN different from a standard FMEA? The math is identical — severity times occurrence times detection — but the failure mode is specifically 'this SKU or component goes to zero on hand.' It reframes classic reliability FMEA thinking for demand and supply planning rather than for a product or process failure.
Should I use the same scale for every item? Yes. The score is only comparable if every SKU is rated on the same defined scale for all three factors. Write down anchored definitions for each level before scoring so two planners rate the same situation the same way.

Last reviewed 2026-05-12.