How do you calculate parts obsolescence risk?

Multiply the three factor scores: financial impact, likelihood of no future demand, and weakness of review controls. With ratings of 7, 5, and 6 the model produces a risk score of about 6.05 on its normalized scale, letting you rank it against other parts.

What makes a part obsolete in MRO inventory?

Usually the asset it serves is retired, redesigned, or upgraded; the manufacturer discontinues the part; or it was over-bought for a failure mode that rarely occurs. The 'likelihood of no future demand' factor captures all of these.

What is a good obsolescence risk score?

Lower is better. There is no universal threshold, but rank your SKUs and set a review trigger at the top decile or two. The default inputs land mid-scale, signaling a part worth watching but not yet an urgent write-off.

Why include detection or control weakness?

Even a high-value, low-demand part is manageable if your process reliably flags it at asset retirement. Weak controls — no link between EAM asset status and storeroom min-max — let exposure build unseen, so they raise the score.

How is this different from a slow-moving inventory report?

A slow-mover report tells you nothing has moved; this scoring adds why it matters (financial impact) and whether your process will catch it (control weakness), so you triage by true exposure rather than by movement alone.

Obsolescence risk score vs. inventory turns?

Turns measure how fast stock cycles overall; this score targets the specific tail of spares at risk of never moving again. Use turns for storeroom-level health and this score for SKU-level disposition decisions.

CMMS, EAM & Spare Parts Management calculator

Parts Obsolescence Risk Calculator

Obsolescence risk is the quiet drain on every MRO storeroom — spares purchased for assets that have been retired, redesigned, or simply never failed, slowly aging into a write-off. This calculator borrows the FMEA logic of severity times occurrence times detection and applies it to inventory: how much money is at stake, how likely it is the part will never be issued again, and how weak your controls are for catching it. Inventory managers, reliability engineers, and MRO planners use the score to triage which slow-moving SKUs deserve a disposition review before they become a balance-sheet liability. The point is to rank, not to compute dollars exactly — so you spend review time where the combined exposure is highest.

What this calculator does

Score the risk that stocked spare parts become obsolete because assets are retired, vendors discontinue parts, or demand disappears.
a maintenance or asset-management team needs to prioritize disposition, supplier returns, standardization, or last-time-buy decisions for a obsolete inventory review
It multiplies three rated factors — financial impact, likelihood of no future demand, and weakness of retirement/demand-review controls — into a single comparable obsolescence risk score.

Formula used

Parts Obsolescence Risk risk score = obsolescence financial impact score × likelihood of no future demand × weakness of asset retirement and demand review controls
Use the same scoring scale across comparable assets, work orders, parts families, and maintenance risk reviews.

Inputs explained

Financial impact of stranded inventory (severity):
Likelihood the part has no future demand (occurrence):
Weakness of retirement and demand-review controls (detection):

How to use the result

Use it during periodic inventory health reviews, asset-retirement events, or annual write-off provisioning to prioritize which parts to investigate first.
It is a relative ranking tool, not an accounting valuation; two parts with the same score can have very different actual carrying costs and disposition paths.

Common questions

How do you calculate parts obsolescence risk? Multiply the three factor scores: financial impact, likelihood of no future demand, and weakness of review controls. With ratings of 7, 5, and 6 the model produces a risk score of about 6.05 on its normalized scale, letting you rank it against other parts.
What makes a part obsolete in MRO inventory? Usually the asset it serves is retired, redesigned, or upgraded; the manufacturer discontinues the part; or it was over-bought for a failure mode that rarely occurs. The 'likelihood of no future demand' factor captures all of these.
What is a good obsolescence risk score? Lower is better. There is no universal threshold, but rank your SKUs and set a review trigger at the top decile or two. The default inputs land mid-scale, signaling a part worth watching but not yet an urgent write-off.
Why include detection or control weakness? Even a high-value, low-demand part is manageable if your process reliably flags it at asset retirement. Weak controls — no link between EAM asset status and storeroom min-max — let exposure build unseen, so they raise the score.
How is this different from a slow-moving inventory report? A slow-mover report tells you nothing has moved; this scoring adds why it matters (financial impact) and whether your process will catch it (control weakness), so you triage by true exposure rather than by movement alone.

Last reviewed 2026-05-12.