Method of Calculating Cost per Minute of a Sewing Line

Question: How we can calculate the cost per minute of a garment sewing line in a very easy way? Show me an easy method of calculating cost per minute of a sewing line. ... asked by Masum

Cost per minute (CPM) calculation method

Normally, the cost per minute of a line is calculated for direct employees. Direct employees like sewing operators, helpers, line supervisors, and quality checkers. 

There are two types of  Cost per Minute measure of a sewing line -
  1. Estimated cost per minute of a line and
  2. Actual cost per minute of a line
As you did not specifically ask which one you need, I am explaining both.

1. Calculate estimated cost per minute (CPM) of a line: 

To use this calculation your operators need to be salaried. The formula used to calculate the Estimated cost per minute

= Total salary of a line for one day / (Total minutes available x Line efficiency%)

To calculate the total salary of a line includes all operators, helpers working in a line. You can also include quality checkers and line supervisors and line feeders if they are not considered under overhead. So, you have to find the following three parameters to calculate the estimated cost per minute of a line.
  1. The total salary of a line for one day 
  2. Total minutes available (daily working minutes) 
  3. Line efficiency% 
Total minutes available = (Number of total workers x Daily working hours x 60)

An example:

The total estimated salary of a typical line is ₹ 6000.00 and total manpower 20 of a 15 machines line and line efficiency 80%.

Cost per minute of the line = (6000 / (20 x 480 x 80%)) = ₹ 0.78

2. Calculating the actual cost per minute of a line 

The formula used to calculate the actual cost per minute of a line

= (Actual salary for the day/ (Total garment produced x SAM))

So, you have to find the following three parameters -
  1. Calculate the actual salary of all operators and other direct labors working on the line in a day
  2. Total pieces made by the line
  3. Garment SAM of the running order

An Example: 

Assume that the total actual salary of a typical production line is ₹ 6000.00, the line made 400 pieces and garment SAM 22 minutes.

Therefore, cost per minute of the line = (6000 / (400 x 22)) = ₹ 0.68


Question-2: 
If a line is loaded with 3 different styles of different SAM. Then how to calculate CPM with formula 2.


I have taken this question from the Facebook comment box. This CPM calculation method when multiple styles are running in a line is shown in this section.

When your line works on 3 different styles in a day, capture the production quantity and garment SAM of the 3 styles. Form the style SAM and produced garments, calculate total SAM produced by the line combined of all 3 styles. Let’s say

Style-1 production Qty – 100 pieces and SAM is 30 minutes
Style-2 production qty – 200 pieces and style SAM is 20 minutes
Style-3 production quantity 100 pieces and style SAM is 10 minutes.

Here total produced minutes = ((100 x 30) + (200 x 20) +(100 x 10)) minutes
= 3000+4000+1000 = 8000 minutes

Let's say the daily salary paid to direct workers is ₹ 6000/-
Therefore, the cost per minute of the line will be =(6000/8000) = ₹ 0.75