Enter the total operational time and the total number of failures into the calculator to determine the mean time between failures (MTBF).
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MTBF Formula
The following formula is used to calculate the mean time between failures.
MTBF = TOT / TF
- Where MTBF is the mean time between failures
- TOT is the total operational time (hours)
- TF is the total number of failures
MTBF Definition
What is MTBF?
MTBF, short for mean time between failures, is a metric used to describe the average time it takes to incur a failure on a piece of equipment.
The equipment can be manufacturing equipment that produces goods or more simply something like an aircondition.
Example Problem
How to calculate MTBF?
- First, determine the total hours of operation.
For this example, we are looking at an air-conditioning unit that has been running for a year straight. This is equal to 8760 hours of operation.
- Next, determine the total number of failures during the time period.
In this case, the air-conditioning failed a total of 5 times.
- Finally, calculate the MTBF.
Using the formula above the mean time between failures is calculated to be:
MTBF = TOT / TF
MTBF = 8760/5
MTBF = 1752 hours/failure
