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Part Number Proliferation Cost Calculator

Duplicate part numbers rarely look expensive because each one costs little. This calculator adds up record maintenance and the extra inventory created by splitting demand across several numbers, and shows the payback of cleaning up.

Your numbers

parts
%

Sample 100 parts and count functional duplicates to estimate this.

$/part/year

Master data upkeep, supplier records, cycle counting and document control.

$/part
%

Additional safety and cycle stock from holding the same function under several numbers.

%/year
$/part

Engineering review, ECO, BOM updates and inventory transfer.

Your results

Total annual cost of duplicates
$168,720
Payback of consolidation
6.5 months
Duplicate parts
960
Annual record maintenance cost
$134,400
Excess inventory from duplicates
$156,000
Annual carrying cost of excess inventory
$34,320
One-time consolidation cost
$91,200

Inputs are estimates. Validate the duplicate share by sampling your item master before presenting the result.

Save results:

Annual duplicate cost vs duplicate share

Sweeps Estimated duplicate or near-duplicate share from 0 to 30, holding your other inputs fixed.

Item master duplicate scan

Optional: we can run an on-prem similarity scan of your item master and hand you a ranked candidate list.

Optional. The tool and every export work without this. No spam.

How to use it

Estimate the duplicate share by sampling. Pick 100 active parts at random and ask engineers how many have an equivalent in the system. Enter the maintenance cost per record from your master data team and the inventory carrying rate from finance. The tool then computes annual cost and payback of a consolidation project.

The formulas

Duplicates equal parts times duplicate share. Annual maintenance is duplicates times cost per record. Excess inventory is duplicates times average stock times the extra-stock percentage, and its carrying cost is that value times the carrying rate. Payback in months equals one-time cleanup cost divided by monthly annual savings.

Reading the result

If payback is under a year, a cleanup project is easy to justify. Longer paybacks may still be worth it when duplicates cause purchasing errors, wrong-part builds or compliance gaps that this model does not price. Use the chart to show how cost scales as new duplicates are added each year.

Common mistakes

Consolidating without a rule to prevent new duplicates only resets the clock. Pair the cleanup with a part numbering policy, a search-before-create step and a classification scheme. Also beware of merging parts that differ in a controlled attribute such as supplier approval or revision.

Frequently Asked Questions

How do I find duplicate parts?

Compare descriptions, manufacturer part numbers, dimensions and classification. Exact matches on manufacturer part number are the easiest. Similarity matching on descriptions finds the rest but needs engineering review before merging.

What does it cost to create a new part number?

Estimates vary by company, but the fully loaded cost including engineering, purchasing, quality and data entry is often a few hundred dollars. Use your own figures in the maintenance and cleanup inputs.

Why does duplication increase inventory?

Demand for one function is split across several numbers, so each needs its own safety and cycle stock. Total stock is higher than for a single number with pooled demand.

Is it safe to merge duplicate parts?

Only after confirming form, fit, function, approved sources and revision. Use an ECO to replace the old number in BOMs, then mark it obsolete or inactive in the ERP.

Netray can run a read-only similarity scan over your item master to estimate the duplicate share and list candidates for engineering review.

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