Free tools/Production & IE
Line Efficiency Calculator
Calculate sewing line efficiency from output, SMV, operators and minutes worked. The line efficiency formula, the operator efficiency formula, a worked example and an efficiency table.
Efficiency
47.2%
Earned minutes
6,800min
The formula
Efficiency % = output x SMV / (operators x minutes worked) x 100. Earned minutes over attended minutes.
Worked example
Output: 800 pcs, Garment SMV: 8.5 min, Operators: 30, Minutes worked: 480 min. Result: Efficiency = 47.2 %; Earned minutes = 6,800 min.
Line efficiency and operator efficiency formulas
Line efficiency % = (output x SMV) / (operators x minutes worked) x 100. The top is the minutes the line earned: every good piece is worth its SMV. The bottom is the minutes the line was paid for.
Worked example: 800 pieces of an 8.5-minute garment earn 6,800 minutes. 30 operators over 480 minutes attend 14,400 minutes. Efficiency = 6,800 / 14,400 x 100 = 47.2%.
Operator efficiency % uses the same formula for one person: (that operator's output x the operation SMV) / (minutes that operator worked) x 100. An operator who sews 400 pieces of a 0.9-minute operation in 480 minutes earns 360 minutes, which is 75%.
Count helpers, ironmen and line feeders in the operator figure only if their minutes are inside the garment SMV. Otherwise the line looks more efficient than it is, or less, depending on which way the mismatch runs.
Line efficiency table (SMV 10, 30 operators, 480 minutes)
| Output (pcs) | Earned minutes | Efficiency % |
|---|---|---|
| 600 | 6000 | 41.7 |
| 720 | 7200 | 50.0 |
| 840 | 8400 | 58.3 |
| 960 | 9600 | 66.7 |
| 1080 | 10800 | 75.0 |
| 1200 | 12000 | 83.3 |
| 1320 | 13200 | 91.7 |
| 1440 | 14400 | 100.0 |
Efficiency for different daily outputs on a 10-minute garment with 30 operators working 480 minutes (14,400 attended minutes), computed with this calculator.
Assumptions
- Off-standard time (meetings, no-feeding) counts against efficiency.
Questions
- What is the formula for line efficiency?
- Line efficiency % = output x SMV / (operators x minutes worked) x 100. For example 800 pieces x 8.5 SMV / (30 x 480) x 100 = 47.2%.
- What is the formula for operator efficiency?
- Operator efficiency % = pieces produced x operation SMV / minutes worked x 100. 400 pieces of a 0.9-minute operation in 480 minutes is 75%.
- Why does my line efficiency look low?
- Every attended minute counts, so waiting for work, machine breakdowns, meetings and style changeovers all lower it. Recording those minutes separately shows where the efficiency went.
- Should I use SMV or SAM in the formula?
- They are the same number. SMV (standard minute value) is the usual term in South Asia and Europe, SAM (standard allowed minute) in the US. Use the garment SMV from a time study or an operation bulletin.
Read the guide
In the platform
Intelactory computes line efficiency from the output and attendance each line records, and forecasts capacity conflicts across lines and factories.