How to use this calculator
- Enter or choose pieces produced.
- Enter or choose operation SMV.
- Enter or choose minutes attended.
- Enter or choose off-standard minutes.
- The on-standard efficiency updates as you type. Use Copy result or Share to keep it.
Method
Earned = Pieces × SMV; On-standard % = Earned ÷ (Attended − Off-standard) × 100; Overall % = Earned ÷ Attended × 100
- Attended
- minutes the operator was at work
- Off-standard
- minutes lost for reasons the operator does not control
Worked example
- Earned = 400 × 1.2 = 480 minutes.
- On-standard = 480 ÷ (480 − 30) = 106.67%.
- Overall = 480 ÷ 480 = 100%.
The operator earned 480 minutes: 106.7% on-standard efficiency and 100% overall after 30 minutes of lost time.
What the result means
On-standard efficiency judges the operator; the gap between on-standard and overall shows how much time management and maintenance lost.
Assumptions and limits
- The SMV is the agreed standard for this operation.
- Rework and quality rejects should be excluded from pieces produced, otherwise efficiency is overstated.
Questions
Can efficiency be above 100%?
Yes. A skilled operator working faster than the standard pace earns more minutes than the time spent.
What counts as off-standard time?
Waiting for work, machine breakdown, power cuts, training and meetings — anything the operator cannot control.