Mean Time Between Failures Calculator

Calculate the average time between failures of a system using MTBF metrics. This calculator is useful for reliability engineering, equipment maintenance planning, and system design.

Input Parameters

Calculation Results

Calculation Formula

MTBF = (Total Operating Hours) / (Total Number of Failures)

Where:
MTBF = Mean Time Between Failures
Total Operating Hours = Sum of all hours the system was in operation
Total Number of Failures = Count of all system failures during operation

MTBF (hours):

0.00

Failures per million hours (FPMH):

0.00

Availability:

0.00%

Mean Time Between Failures Calculator Usage Guide

Learn how to use the MTBF calculator and understand reliability metrics for your systems

What is MTBF?

Mean Time Between Failures (MTBF) is a measure of system reliability. It represents the average time a system operates without failure. A higher MTBF indicates a more reliable system.

How to Use This Calculator

  1. Enter the total number of failures your system experienced during a specific period
  2. Input the total operating hours during that same period
  3. Specify the average operating hours per day
  4. Enter the number of operating days per week
  5. Click "Calculate" to see the results

Understanding the Results

  • MTBF (hours): The average time between failures in hours
  • Failures per million hours (FPMH): A measure of reliability where 1 failure per million hours is considered excellent
  • Availability: The percentage of time the system is operational

Example Application

Suppose a server had 5 failures over a period of 8,760 hours of operation (24/7). The MTBF would be 1,752 hours between failures. This information can help in planning maintenance schedules and assessing system reliability.

Reliability Metrics Context

MTBF is often used alongside Mean Time To Repair (MTTR) to calculate system availability using the formula: Availability = MTBF / (MTBF + MTTR). For highly reliable systems, a larger portion of the time is available for operation.