FMEA RPN Calculator

FMEA = Failure Mode and Effects Analysis. RPN = Risk Priority Number. Calculates RPN (Severity × Occurrence × Detection) for each failure mode, ranks them by priority, and flags any failure mode with high severity regardless of its overall RPN score.

High-Priority RPN Threshold Organization-specific — there is no universal standard cutoff. 100–125 is a commonly used starting point.

Failure Modes

Highest RPN

Failure Modes Above Threshold

Formula Reference

RPN = Severity (S) × Occurrence (O) × Detection (D), each rated 1–10. Maximum possible RPN = 1000.

Generic Rating Anchors (1–10 scale)

Severity	1 = no effect → 10 = hazardous, without warning
Occurrence	1 = failure unlikely → 10 = failure almost inevitable
Detection	1 = almost certain to detect → 10 = no known way to detect

Why RPN Alone Isn't Enough

A failure mode with Severity 9–10 (safety or regulatory hazard) can still produce a modest RPN if Occurrence and Detection happen to be low — but most FMEA methodologies (including AIAG-VDA's newer Action Priority approach) treat high severity as requiring action regardless of the overall RPN score. This calculator flags any Severity ≥ 9 failure mode separately from the RPN ranking for this reason.

Methodology, interpretation & sources

Purpose. FMEA = Failure Mode and Effects Analysis. RPN = Risk Priority Number. Calculates RPN (Severity × Occurrence × Detection) for each failure mode, ranks them by priority, and flags any failure mode with high severity regardless of its overall RPN score.

How to use the result. Start with source data you can verify, enter values on a consistent unit and time basis, and record the assumptions used. The main inputs on this page include High-Priority RPN Threshold Organization-specific — there is no universal standard cutoff. 100–125 is a commonly used starting point., Your Name, Email, Company Name, What Calculator/Tool Do You Need?. Re-run the calculation when those assumptions change rather than carrying an old result forward.

Decision use. Use this calculator as a structured process-safety screening aid. It does not replace a formal PHA, QRA, LOPA or competent engineering review when those methods are required.

Limitations. Event definitions, consequence assumptions, exposure frequencies, safeguards and uncertainty should be documented so that the result can be independently reviewed.

Primary references. Use the current edition/version that applies to your jurisdiction and organization:

Editorial note. Prepared and maintained by Impact Tech Solutions. Editorially updated 28 September 2026. No individual professional credential is claimed on this page; high-consequence, statutory, tax, engineering or health decisions should be independently verified against the current primary source and, where required, a qualified professional.