ERP & MRP Planning worked example

MRP Material Requirements with gross material requirement of 3,100 units: a worked example

This scenario runs the mrp material requirements calculation on the strong side: gross material requirement of 3,100 units, with every other input held at its documented default. an MRP planner needs to decide how many components or finished units still need planned supply

The inputs for this scenario

  • Gross material requirement: 3,100 units (raised for this scenario; the documented default is 1,250)
  • Available on-hand inventory: 420 units (unchanged)
  • Open PO or work-order receipts: 300 units (unchanged)
  • Approved substitute or reserved supply: 80 units (unchanged)

Working through the calculation

  • Applying the documented formula (Net material requirement = gross material requirement - available on-hand inventory - open receipts - approved substitute or reserved supply) to the inputs above produces each figure below.
  • At this operating point the engine returns 2,300 units for net material requirement, the number this scenario is built around.
  • At this operating point the engine returns 800 units for total usable supply before requirement date.
  • At this operating point the engine returns 3,100 units for gross material requirement.
  • At this operating point the engine returns 74.19 % for supply coverage of gross requirement.

How this compares with the baseline

  • Against the tool's baseline example, where gross material requirement sits at 1,250 units and the headline result is 450 units, this scenario comes in 411% above the baseline at 2,300 units.
  • Use it whenever you net a part during MRP planning, before releasing a planned purchase order or work order, or when validating what an ERP run actually proposed. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Net material requirement: 2,300 units (headline result)
  • Total usable supply before requirement date: 800 units
  • Gross material requirement: 3,100 units
  • Supply coverage of gross requirement: 74.19 %

Run it with your numbers

  • Every input above is editable in the live MRP Material Requirements calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.