Product Warranty Value Calculator
Estimate the expected monetary value of a product warranty based on failure rate, repair/replacement costs, warranty duration, and discount rate.
Percentage of units expected to fail per year (industry/manufacturer data)
Average cost to repair or replace a failed unit
Time value of money / cost of capital (e.g. 5%)
Overhead for processing warranty claims (typically 10–20%)
Total units covered under warranty
Results will appear here.
Formula
Expected Warranty Value (per unit, present value):
EWV = Σt=1T [ p × (1−p)t−1 × Ctotal ] / (1+r)t
Where:
- p = Annual failure rate (decimal)
- T = Warranty duration in years
- Ctotal = Repair cost × (1 + admin overhead rate)
- r = Annual discount rate (decimal)
- p × (1−p)t−1 = Probability of first failure occurring in year t (geometric distribution)
- Cumulative Failure Probability = 1 − (1−p)T
- Fleet Liability = EWV × Units Sold
Assumptions & References
- Failures follow a geometric (discrete exponential) distribution — constant annual failure rate, memoryless property.
- Each unit can fail at most once during the warranty period (first-failure model); repeat failures are not modeled.
- Repair/replacement cost is assumed constant across all years (no inflation adjustment).
- Administrative costs typically range from 10–20% of repair cost (APQP / warranty management industry benchmarks).
- Discount rate reflects the cost of capital or risk-free rate (e.g., U.S. Treasury rate + risk premium).
- Annual failure rates can be sourced from MTBF (Mean Time Between Failures) data: p ≈ 1 − e−1/MTBF.
- Reference: ASC 460 (Guarantees) and IAS 37 (Provisions) govern warranty liability accounting recognition.
- For complex products, consider using Weibull distribution models for more accurate failure rate modeling over time.