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Garment Costing Calculator
Full garment cost sheet — fabric, trims, CM, overhead and profit.
CostNest Calculator
CM Calculator — Cost of Making per Garment
Derive the exact Cost of Making (CM) per garment from SAM, operator wage rate, line efficiency and factory overhead. Follows the SAM-based IE methodology used in Bangladesh RMG factories. Enter monthly salary in BDT or a direct minute wage. No account needed — numbers update as you type.
CM accuracy depends entirely on SAM quality. SAM values derived from proper time study (ILO-recommended 3-cycle minimum at 100 BSI rating) produce reliable CM figures. Guessed SAM leads to systematic underpricing.
Step By Step
How to Use This Calculator
6 steps
- Enter the SAM for this style — get it from your IE department's time study sheet, not from memory.
- Enter line efficiency as a percentage. Use the last 5-day rolling average from your production report, not best-ever efficiency.
- For minute wage: either enter it directly (basic salary ÷ monthly working minutes), or enter the monthly basic salary and let the tool convert it.
- Set working minutes per day — standard is 480 min (8 hr shift) but use 450 if your factory deducts two 15-min breaks.
- Set overhead as a percentage of direct labour — typically 20–35% covering supervisors, IE, electricity, machine depreciation.
- Add your target profit margin on CM to get the total CM you quote to the buyer.
Worked Example
Worked example — Polo shirt, Grade 5 operator, Bangladesh
Use this sample to sanity-check your inputs and understand what the final result represents.
- 1SAM: 18.5 min (from time study) · Line efficiency: 62% (5-day rolling average)
- 2Monthly basic salary: BDT 8,470 (Grade 5 minimum, Dec 2023 gazette)
- 3Working minutes per month: 26 days × 480 min = 12,480 min
- 4Minute wage: BDT 8,470 ÷ 12,480 = BDT 0.6787/min
- 5Labour cost: (18.5 ÷ 0.62) × 0.6787 = BDT 20.25
- 6Overhead 30%: BDT 6.08 → Direct CM: BDT 26.33
Final Result
Total CM at 10% profit: BDT 29.25/pc ≈ $0.266 at 110 BDT/USD.
Methodology
CM Formula — ILO / REFA standard
This section explains the calculation logic, assumptions, and source material used to make the result more trustworthy and easier to verify.
Minute Wage = Monthly Basic Salary ÷ (Working Days × Minutes per Day). Labour Cost per Piece = (SAM ÷ Line Efficiency) × Minute Wage. Overhead Amount = Labour Cost × Overhead%. Direct CM = Labour Cost + Overhead. Total CM = Direct CM × (1 + Profit%). Daily Output = (Working Minutes × Efficiency) ÷ SAM. Source: ILO Work Study (4th ed.), Chapter 19; REFA Methodology for Work Measurement; Bangladesh BGMEA Industrial Engineering Guidelines 2022.
Practical Guidance
How IE professionals calculate reliable CM
- 1SAM must come from formal time study with a minimum 3 cycles per operation at 100 BSI performance rating — the ILO Work Study manual specifies this
- 2Never use 'best-day efficiency' for costing — it produces a CM that is only achievable under ideal conditions; use a 5-day rolling average instead
- 3Add a learning curve allowance of 10–15% to CM for the first 2 weeks of a new style — output will be 40–55% of steady-state during that period
- 4Machine depreciation, electricity and maintenance typically add 8–12% to direct labour cost — include these in your overhead base
- 5Bangladesh average line efficiency across all product categories is 55–65% per the BGMEA IE survey 2023; world-class lines achieve 75–85%
- 6For multi-operation styles, CM = sum of each operation's (SMV × wage rate ÷ efficiency); don't use a single blended SAM across departments
Frequently Asked Questions
What is SAM and how is it measured correctly?+
SAM (Standard Allowed Minutes) is the time a qualified worker, trained to standard method and working at 100 BSI performance, needs to complete one garment — including personal, fatigue and delay (PFD) allowances (ILO recommends 15–20% PFD for sewing). It is measured by industrial engineers using direct time study (stopwatch, minimum 3 observations per operation per the ILO Work Study manual, 4th edition), or by synthetic data systems such as MOST (Maynard Operation Sequence Technique) or MTM-2. A valid SAM is the single most important input for accurate CM.
Why does line efficiency matter more than operator speed?+
Individual operator speed only matters to the extent the whole line can absorb it. A fast sewing operator blocked by slow preceding operations produces idle time, not more output. Line efficiency captures the system-level loss — balancing losses, material delays, machine downtime, quality holds and absenteeism. The ILO Work Study manual (Chapter 22) defines line balance efficiency as total SAM produced ÷ total available time for all operators. Improving line balance from 60% to 70% reduces CM by 14% without changing a single wage.
What overhead percentage should I use for CM?+
Overhead in CM covers costs that cannot be assigned to a single garment: floor supervisors, IE engineers, quality inspectors, machine maintenance, electricity, building lease and depreciation. For Bangladesh RMG factories, a 20–30% overhead rate on direct labour is typical for mid-size factories (500–2,000 workers). Smaller factories often have higher rates (30–40%) because fixed overhead is spread across fewer pieces. Calculate your actual overhead rate quarterly: total monthly overhead cost ÷ total direct labour cost × 100.
How do I convert monthly salary to a minute wage?+
Minute wage = Monthly basic salary ÷ (Working days per month × Working minutes per day). The Bangladesh RMG standard is 26 working days × 480 minutes = 12,480 minutes per month. For a Grade 5 worker on BDT 8,470 basic: minute wage = 8,470 ÷ 12,480 = BDT 0.6787/minute. Note: only the basic salary component is used for CM — house rent, medical, transport and food allowances are included in overhead, not direct labour, per BGMEA costing convention.
Should CM include profit, or is profit added separately?+
Industry practice varies. Some factories quote direct CM (labour + overhead only) and add profit in the cost sheet separately under 'factory margin'. Others bundle profit into the CM line. The BGMEA standard cost sheet separates direct CM from profit so that buyers can see the factory's cost base. The CM Calculator shows both: direct CM and total CM including profit. When negotiating with buyers, disclose the direct CM if asked; keep the profit component internal.