Duplicate path
Flag the same parent-child row entered twice. Decide whether it is a true repeat at different positions or accidental duplication.
Multi-level BOM workbook
Explode a multi-level BOM and see the rolled-up requirement
See how subassembly quantities multiply down a structure and how the same component rolls up across two paths. Download the working XLSX before replacing the fictional monitor assembly with your own.
Sign in to inspect fictional sample records. Copy the app before adapting it to live product data.
Calculated example
Follow the path from finished product to total component demand
The sample proves the formulas
- Motor assemblies
- 20
- Housing assemblies
- 20
- Shared screws
- 160
- Material rollup
- $564.20
Understand the calculation before trusting the total
Build quantity×Quantity at level 1×Quantity at level 2=Required component quantity
The structure sheet retains each parent-child path. The rollup sheet groups the resulting component requirements, so a screw used in both the motor and housing assemblies is counted from both paths.
Workbook checks
Catch structural mistakes that make a neat total unreliable
Missing parent
Reject a lower-level row whose parent does not exist in the structure. An orphan cannot inherit a valid path quantity.
Circular structure
Stop a component path that eventually points back to itself. Circularity makes the required quantity undefined.
Do not mistake a BOM explosion for material planning
What this workbook answers
What components are structurally required for the fictional build, and what do the entered unit costs sum to?
What it does not answer
What is on hand, allocated, scrapped, already ordered or due from a supplier. For that, connect an approved BOM to raw-material inventory and production planning in the system that owns those transactions.
Use the result safely
Turn the exploded list into a controlled planning input
Freeze the calculation basis
Record the finished item, revision and requested build quantity with the exported requirements. A total without those three references cannot be reproduced or compared later.
Resolve unit and sourcing exceptions
Confirm that purchasing units, scrap factors and substitute parts are handled by the receiving planning system. The workbook uses the structure quantities and unit costs shown in the file; it does not infer those operating rules.
Compare demand with live supply
Send leaf-part requirements to the inventory or MRP process that owns on-hand stock, open orders and lead times. Keep BOM approval separate from the decision to buy or schedule material.
Practical questions
Multi-level BOM template questions
What makes a BOM multi-level?
A finished item contains subassemblies, and those subassemblies contain components of their own. The required quantity for a lower-level component depends on every quantity along its parent path.
What does the workbook calculate?
It multiplies quantities down each structure path, applies the requested top-level build quantity, aggregates repeated components and rolls up entered unit costs. It also flags duplicate paths, missing parent rows and circular parent relationships.
Can this workbook replace an MRP explosion?
No. It is an inspectable planning aid for one example structure. It does not consider inventory, scrap, lead time, effective dates, alternate materials, lot sizing or open supply.
Why can the same component appear more than once?
A common fastener or label may be used in several subassemblies. The structure sheet retains each path; the rollup sheet aggregates the total requirement so purchasing does not count only one occurrence.
When is specialist BOM software safer than Excel?
Use a controlled system when structures are deep, several revisions are effective at once, engineering and manufacturing BOMs differ, or approved changes must update planning and inventory transactions.