MRP Planner Exception Workload Calculator
Exception messages are the planner's work queue. When the queue grows faster than it is cleared, planners ignore the system. This calculator shows whether the workload fits the team.
Your numbers
Include checking the order, calling the supplier and updating the system.
After meetings, expediting calls and other duties.
Your results
A planning aid, not a staffing standard. Complexity differs by item class, so run it separately for A, B and C items if you can.
Utilization vs weekly exception rate
Sweeps Items with an exception each week from 1 to 40, holding your other inputs fixed.
Exception message analysis
Optional: we can review your exception history and show which causes create the most planner work.
Optional. The tool and every export work without this. No spam.
How to use it
Enter the number of active planned items, current planners, the share of items that generate an exception in a typical week, minutes to resolve one, and hours per planner actually available for exceptions. Pull the exception rate from your MRP output log over several weeks. The result shows hours needed against hours available and the planner count required.
- Measure exception rate over at least four weeks.
- Time real exception handling instead of guessing.
- Subtract meetings and expediting from available hours.
The method
Exceptions per week equal items times the exception rate. Hours needed equal exceptions times minutes each, divided by 60. Utilization equals hours needed divided by hours available. Planners required equals hours needed divided by the productive hours per planner, rounded up. The chart sweeps the exception rate, which is the lever most under your control through parameter tuning.
Reading the result
For 4,500 items at a 12 percent rate, there are 540 exceptions a week. At 9 minutes each that is 81 hours against 96 available, or about 84 percent utilization, so four planners just cope. Raise the rate to 20 percent and the load reaches 140 percent, which means five planners are needed or the exception rate must come down.
Reducing the load
Cutting exceptions is usually cheaper than hiring. Clean up lead times, remove reschedule messages with tolerances, review lot sizes that cause cancel and reschedule noise, and fix inaccurate inventory. Assign items to planners by class so complexity is balanced. A high rate that never falls usually points to master data problems rather than a real planning workload.
Frequently Asked Questions
What is a normal exception rate?
It varies widely with data quality and demand stability. Rates of 5 to 15 percent of items per week are common in stable environments, and much higher when data is poor.
How many items can one planner manage?
There is no universal figure. It depends on item complexity, supplier count and automation. Use measured handling time, as this tool does, instead of a fixed ratio.
Why do exceptions keep growing?
Common causes include outdated lead times, unrealistic demand forecasts, inaccurate stock and tight reschedule tolerances. Each generates messages that planners must open and close.
Can AI help reduce planner workload?
It can group and prioritize exceptions and draft supplier messages, and a simpler rule based filter may be enough for many sites. Human approval should stay on changes to orders.
Netray can analyze your exception history, group messages by cause, and show which parameter changes would remove the most noise.
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