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Failure Rate Formula:
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Failure Rate (FR) represents the frequency at which an engineered system or component fails, expressed as failures per unit time. It is the reciprocal of Mean Time Between Failures (MTBF) and is a key metric in reliability engineering and maintenance planning.
The calculator uses the fundamental reliability formula:
Where:
Explanation: This relationship shows that as MTBF increases (system becomes more reliable), the failure rate decreases proportionally.
Details: Calculating failure rate is essential for predicting system reliability, planning maintenance schedules, estimating spare parts requirements, and making informed decisions about system design and replacement strategies.
Tips: Enter the Mean Time Between Failures in any consistent time units (hours, days, years, etc.). The calculator will return the corresponding failure rate in failures per the same time unit.
Q1: What Is The Difference Between MTBF And Failure Rate?
A: MTBF represents the average time between failures, while failure rate represents how often failures occur. They are mathematically reciprocal: FR = 1/MTBF.
Q2: What Time Units Should I Use?
A: Use consistent time units that make sense for your application. Common units include hours for electronic components, days for mechanical systems, or years for long-life equipment.
Q3: Can Failure Rate Change Over Time?
A: Yes, failure rates often follow a "bathtub curve" - high during early life (infant mortality), low during useful life, and increasing during wear-out phase.
Q4: How Accurate Is This Calculation?
A: This provides a theoretical failure rate based on historical MTBF data. Actual failure rates may vary due to operating conditions, maintenance quality, and environmental factors.
Q5: What Are Typical Failure Rate Values?
A: Failure rates vary widely by industry and component type. High-reliability systems might have failure rates below 0.0001 failures/hour, while less critical systems may have higher rates.