SAH & CU Calculator (Apparel / Production Planning)
Use this tool to calculate SAH (Standard Allowed Hours) and CU (Capacity Utilization) for a production line or factory floor.
What is an SAH CU calculator?
A SAH CU calculator helps production teams convert operational data into two very useful metrics: SAH (Standard Allowed Hours) and CU (Capacity Utilization). These numbers are widely used in apparel manufacturing, sewing lines, and labor-intensive production environments where planning labor and output accuracy matters.
If you already track unit output and SAM values, this calculator gives you a fast way to answer practical questions: Are we underutilized? Are we overloaded? How many people do we need at our target utilization? What output can we expect at a realistic CU target?
Core formulas used in this calculator
1) SAH (Standard Allowed Hours)
SAH = (Units Produced × SAM) ÷ 60
SAM is usually measured in minutes, so dividing by 60 converts total standard minutes into standard hours.
2) Available Capacity Hours
Capacity Hours = Manpower × Working Hours/Day × Working Days
This is your total available labor time for the period, assuming full attendance and full assignment.
3) CU (Capacity Utilization)
CU (%) = (SAH ÷ Capacity Hours) × 100
CU tells you how much of your available labor capacity was consumed by standard work content.
- CU below 70% often signals unused capacity, line imbalance, poor loading, or excessive downtime.
- CU between 75% and 90% is commonly considered a healthy operating range (varies by factory maturity).
- CU above 100% can indicate overtime, unrealistic SAM, data errors, or unsustainable pace.
How to use this tool correctly
Step-by-step
- Enter the actual units produced during the selected period.
- Enter the product or blended line SAM per unit.
- Provide manpower, working hours, and number of working days for the same period.
- Set a target CU% (for example, 80% to 90%).
- Click Calculate to get SAH, CU, suggested manpower at target CU, and expected output at target CU.
Why SAH and CU are valuable for planning
Many teams track output only in pieces. That is useful but incomplete. Two lines can make the same quantity with completely different work content. SAH standardizes production into time, making comparison fair across styles and complexity.
CU then links that work content to your labor capacity. This helps with:
- Daily and monthly line loading decisions
- Hiring and manpower balancing
- Target setting with realistic expectations
- Style allocation based on line capability
- Early identification of over/under capacity
Example scenario
Suppose a line made 1,200 units of a style with SAM 22.5. Manpower is 45, working 8 hours/day for 26 days.
- SAH = 1,200 × 22.5 ÷ 60 = 450 hours
- Capacity Hours = 45 × 8 × 26 = 9,360 hours
- CU = 450 ÷ 9,360 × 100 = 4.81%
This CU is extremely low, indicating either the input period/style mix is mismatched, SAM/units are not aligned, or most capacity was assigned elsewhere. This is exactly why the calculator is useful: it quickly highlights when something in planning or data needs review.
Common mistakes to avoid
1) Mixing time periods
If units are for one week but manpower/hours are for one month, CU will be misleading. Keep all inputs from the same period.
2) Using outdated SAM values
Old or unvalidated SAM values distort SAH. Re-check SAM after method changes, machine changes, or significant learning curve effects.
3) Ignoring non-sewing support time
If manpower includes roles not reflected in standard minutes, CU may appear lower than expected. Define your manpower base consistently.
4) Treating CU as the only KPI
CU is powerful, but it should be read along with quality, on-time delivery, absenteeism, and rework rates.
Frequently asked questions
Is a higher CU always better?
Not always. Very high CU can be a warning sign of overloading, rushed work, and potential quality issues. Sustainable performance is usually better than peak short-term numbers.
Can I use blended SAM for multiple styles?
Yes. If you produce multiple styles, a weighted average SAM is a practical approach, especially for monthly planning.
What target CU should I choose?
Many operations start around 75% to 85% and improve over time through better balancing, operator training, and workflow standardization.
Final takeaway
A reliable SAH CU calculator turns raw production numbers into decisions. Use it regularly for line loading, target planning, and manpower discussions. When your SAH and CU are visible, productivity conversations become objective and actionable.