Capacity Requirements Planning Calculator

About the Capacity Requirements Planning Calculator

Capacity Requirements Planning (CRP) is a detailed capacity validation tool that sums the hours from all planned and released production orders at each work center for each time period. Unlike rough-cut capacity planning (RCCP), CRP uses actual routing data and order quantities for precise load calculations.

CRP answers the question: given all the orders we plan to run and are already running, do we have enough capacity at each work center in each week? It provides a work-center-level, period-by-period load profile that shows exactly where and when capacity constraints will occur.

This calculator performs a simplified CRP for one work center, letting you enter planned order hours and released order hours, then comparing the total against available capacity. It shows load percentage, overload, and remaining capacity.

Precise measurement of this value supports data-driven planning and helps manufacturing professionals make informed decisions about resource allocation and process optimization strategies. Quantifying this parameter enables systematic comparison across time periods, shifts, and production lines, revealing patterns that might otherwise go unnoticed in routine operations.

When This Page Helps

CRP catches detailed capacity problems that RCCP misses. By using actual order data and routings, it provides the most accurate picture of whether your production plan is executable at each work center.

How to Use the Inputs

1. Enter the total hours from planned orders at the work center.
2. Enter the total hours from released (open) orders at the work center.
3. Enter the available capacity in hours for the work center in the period.
4. View total load, load percentage, and capacity position.
5. If overloaded, adjust order timing, add overtime, or re-route work.
6. Run CRP weekly as MRP regenerates planned orders.

Example Calculation

Tips & Best Practices

• Include both setup and run time in order hours — setup can be significant.
• Check CRP at each key work center, not just the known bottleneck.
• Allow for efficiency factors if historical performance differs from standard.
• Look ahead at least 4-8 weeks to catch problems early enough to resolve.
• Use CRP to validate MRP output before releasing orders to the shop floor.
• Combine CRP data from all products sharing a work center.

CRP Data Flow

CRP pulls data from three sources: (1) planned orders from MRP, (2) released orders from the shop floor control system, and (3) work center capacity from the capacity calendar. The intersection of these three data sources produces the CRP load profile.

Infinite vs. Finite Loading

Standard CRP performs infinite loading — it piles all orders onto the work center timeline regardless of capacity limits. Finite loading then levels the load by moving orders to periods with available capacity. Most ERP systems offer both views.

CRP and Shop Floor Feedback

CRP accuracy depends on production reporting. When operators report completions, released order hours decrease. Late reporting makes CRP show more load than actually exists. Ensure timely production reporting for accurate CRP.

Frequently Asked Questions

• What is the difference between CRP and RCCP?

  RCCP uses MPS quantities and aggregate load factors for quick validation. CRP uses detailed planned and released order data with actual routing times. CRP is more accurate but requires MRP to have run first.

• When should I use CRP vs. RCCP?

  Use RCCP first to validate the MPS before running MRP. After MRP generates planned orders, use CRP to validate the detailed capacity implications. Both are needed — they serve different stages of planning.

• What are planned vs. released orders?

  Planned orders are generated by MRP but not yet committed — they can be changed freely. Released orders are committed and usually have materials allocated and a shop packet. Both consume capacity.

• How do I fix a CRP overload?

  Options include: delaying non-urgent planned orders, using alternate routings, splitting orders across periods, adding overtime, outsourcing, or negotiating delivery date changes with customers. Documenting the assumptions behind your calculation makes it easier to update the analysis when input conditions change in the future.

• Does CRP account for order priority?

  Basic CRP sums total hours without regard to priority. Advanced scheduling systems layer in priority-based sequencing. For simple CRP, manually check that high-priority orders have capacity first.

• How often should I run CRP?

  Run CRP every time MRP regenerates — typically weekly for full regeneration and daily for net-change updates. The fresh CRP report reflects the latest order changes.