Maintenance program
Wrench time calculator
Wrench time is the share of a paid shift a technician spends with hands on the asset. Travel, waiting for a permit, looking for a part and hunting down a drawing are all real work, but none of it is productive work, and that is usually where most of the day goes.
Wrench time = Hands-on tool time ÷ Total paid time × 100
Summed across the crew for the period
Show the assumptions
- Formula
- Wrench time = Hands-on tool time ÷ Total paid time × 100
A low figure is a planning finding, not a performance review. Technicians rarely control travel distance, permit queues or whether the part was on the shelf, and treating wrench time as an individual metric is the fastest way to make the data unreliable.
Wrench time
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Prefilled with an example. Change any number and the result updates.
How to calculate Wrench time
Wrench time = Hands-on tool time ÷ Total paid time × 100
Worked example
- Hands-on tool time 72 hrs
- Total paid time 240 hrs
Wrench time = 30.0%
Reading the result
A low figure is a planning finding, not a performance review. Technicians rarely control travel distance, permit queues or whether the part was on the shelf, and treating wrench time as an individual metric is the fastest way to make the data unreliable.
Benchmarks
25% to 35% is what most sites measure. Above 50% is commonly cited as best in class and generally requires a planner, a kitted stores function and pre-staged parts.
Wrench time questions
What counts as wrench time?
Time physically working on the asset, including diagnosis at the machine. Travel, permits, toolbox talks, waiting on stores, retrieving drawings and paperwork do not count, even though the job cannot happen without them.
How do I measure wrench time without following people around?
Work sampling is the usual method: random observations across a shift, classified as tool time or not, then extrapolated. Time recorded on work orders tends to overstate wrench time, because technicians log the job duration rather than the productive portion of it.
Is low wrench time the technicians’ fault?
Almost never. The main causes are work that was not planned before it was issued, parts that were not staged, and permits that were not raised in advance. All three sit upstream of the person holding the wrench.
Related calculators
Give technicians the job in their pocket
UpKeep records the work, the hours and the failures this metric depends on, so Wrench time is a report rather than a spreadsheet exercise.