Line efficiency formula
Efficiency % = (Output × SMV) ÷ (Operators × Working minutes) × 100
Produced minutes (output × SMV) show how much standard work the line delivered. Available minutes (operators × working minutes) show how much time you paid for. Efficiency is the ratio of the two.
Worked example
A line of 20 operators works 480 minutes and produces 1,000 polo shirts with an SMV of 5.0. Produced minutes = 5,000. Available minutes = 9,600. Efficiency = 5,000 ÷ 9,600 × 100 = 52.1%.
How to improve line efficiency
- Find the bottleneck with a stopwatch or video time study and rebalance operations.
- Match operators to operations using a skill matrix.
- Reduce non-productive time: machine breakdowns, waiting for bundles, rework.
- Verify your SMV — an inaccurate SMV makes efficiency look better or worse than it really is.
Frequently asked questions
How do you calculate sewing line efficiency?
Line efficiency % = (total output × SMV) ÷ (number of operators × working minutes) × 100. For example, with 1,000 pieces of a 5.0 SMV garment and 20 operators over 480 minutes, efficiency is 52%.
What is a good line efficiency in garment manufacturing?
Many garment lines run between 50% and 70%. Lines above 85% are considered excellent, while lines below 60% usually have balancing, absenteeism or quality issues worth investigating.
What is SMV?
SMV (Standard Minute Value) is the time in minutes a trained operator needs to complete an operation or garment at a normal pace, including allowances. It is usually set with GSD, PMTS or a time study.
What is the difference between operator and line efficiency?
Operator efficiency compares one person's produced minutes to their attended minutes. Line efficiency does the same for the whole team, so it also reflects balancing and waiting time.