Bill of Materials (BOM) & Costing

Know Every Part and Its Cost Before You Start Production

One cabinet. Every part. A clearer material plan.

A product may look simple when it is finished. But behind it are sheets, fittings, smaller assemblies, labour and many small costs.

YourOrderBook helps manufacturers organise Bills of Materials (BOMs), plan material quantities and understand estimated production costs using connected Frappe/ERPNext processes.

Explore the Cabinet BOM Discuss My Manufacturing Process

Take Apart a Cabinet. See What Goes Into Making It.

This example uses a two-door steel storage cabinet. Start with one finished product, open it up, and explore the parts inside. Then choose how many cabinets to make.

Inside a Storage Cabinet

Sample model CAB-STD-01 | Two doors | Three shelves

AssembledExploded

Select a part to see what it needs and how it contributes to the estimated cost.

BOM structure

1100
- 1 per cabinet100
  - 12 kg1,200 kg
  - 2 m200 m
- 2 per cabinet200
  - 4 kg per door800 kg
  - 2 nos per door400 nos
  - 1 no per door200 nos
- 3 nos300 nos
- 1 set100 sets
- 1 kit100 kits
- 1 kit100 kits

Assemblies group their parts. Each raw material is counted once.

100 cabinets planned

Materials per cabinet: ₹4,240
Operations per cabinet: ₹900
Estimated cost per cabinet: ₹5,140
Estimated total for this run: ₹5,14,000

Material estimate + operation estimate = sample manufacturing estimate.

Full material list and operations

Raw materials, each counted once (exploded from the assemblies)
Material	Per cabinet	Sample rate	Per cabinet	For 100 cabinets
Body sheet metal	12 kg	₹95/kg	₹1,140	₹1,14,000
Reinforcement profile	2 m	₹130/m	₹260	₹26,000
Door sheet metal	8 kg	₹95/kg	₹760	₹76,000
Hinges	4 nos	₹90/no	₹360	₹36,000
Handles	2 nos	₹150/no	₹300	₹30,000
Shelves	3 nos	₹290/no	₹870	₹87,000
Lock set	1 set	₹280/set	₹280	₹28,000
Fastener kit	1 kit	₹110/kit	₹110	₹11,000
Packing kit	1 kit	₹160/kit	₹160	₹16,000
Material estimate			₹4,240	₹4,24,000

Sample operations, per cabinet
Operation	Planned time	Sample hourly rate	Per cabinet	For 100 cabinets
Cutting and bending	45 minutes	₹400/hour	₹300	₹30,000
Assembly	40 minutes	₹360/hour	₹240	₹24,000
Finishing / handling	30 minutes	₹720/hour	₹360	₹36,000
Operation estimate			₹900	₹90,000

This simple example does not include setup costs, bulk prices, coating materials, tooling, taxes, transport or every overhead.

Extra steel is a sample planning allowance for sheet-metal input. It does not represent a universal wastage rule or automatically update your ERPNext BOM.

Demonstration only. Example quantities and rates, not live ERP data, confirmed supplier prices, taxes, selling prices or actual manufacturing costs.

A Good BOM Answers More Than "Which Parts Do We Need?"

Know the right quantity. If an order grows from 25 cabinets to 100, the material requirement should grow with it.
See smaller assemblies clearly. A door is one assembly, but it still needs steel, hinges and a handle. The details should not get lost.
Check costs before work begins. A changed material rate can affect the estimated cost of every finished unit.
Give every team the same starting point. Planning, purchasing and production work better when they use the correct product structure and quantities.

See how production planning works

One Finished Product Can Have Many Levels

A cabinet has doors. Each door has its own steel, hinges and handle. That is a simple example of a multi-level BOM.

Open the door assembly in the example to see its parts. The full material list can also show the materials inside smaller assemblies.

A sub-assembly can have its own BOM. The exploded materials view helps you see the underlying raw materials without counting the assembly twice.

Finished cabinet×1

Body assembly
- 12 kg body steel
- 2 m reinforcement
Door assembly (2)
- 4 kg door steel
- 2 hinges
- 1 handle
per door
Shelves and fittings
- 3 shelves
- 1 lock set
- 1 fastener kit
- 1 packing kit

Raw materials inside each assembly

For 100 cabinets:200 door assemblies · 800 kg door steel · 400 hinges · 200 handles

Estimated Material Cost Is Not the Final Job Cost

A BOM can give you a useful starting estimate. It may include raw-material values and planned operation time, depending on the information you maintain.

Actual production can be different. Material consumed, work completed, additional expenses and recorded operation time all matter.

Before production
Material estimate
₹4,240
Parts and quantities multiplied by their sample rates.
Operation estimate
₹900
Planned time and hourly rates for manufacturing work.
Estimate per cabinet
₹5,140
From the cabinet example above
When work takes place
- Actual quantity used
- Time and extra costs
After work is recorded
Actual production records
What the business later records during manufacturing. This is not shown by our public demo.
Actual cost depends on recorded work

Rates and costing depend on the company's ERPNext setup. A BOM estimate is not a customer quotation or a final profit figure.

When a Part Changes, the BOM Needs Attention Too

Suppose the team chooses a different hinge. The change may affect the item, quantity, price or how the product is assembled.

Keep a clear record of the approved product structure. Review which future jobs should use the revised BOM rather than quietly changing the past.

1Current BOM
BOM rev A
Door assembly
Hinge, standard · ₹90 each2 per door
Door sheet metal · 4 kg
Handle · 1
2Review the part change
Reviewed by the team
3Revised BOM
Proposed rev B
Door assembly
Hinge, revised · ₹110 each2 per door
Door sheet metal · 4 kg
Handle · 1
4Check future production work
- Completed jobs stay as recorded
- Choose which new jobs use rev B

Submitted BOM changes follow the system's document and revision controls. Existing work orders and stock transactions do not change automatically because this website animation changed a value.

Make Your BOM Useful Beyond a Spreadsheet

We start with how your products are made today. Then we help structure the items, assemblies, operations and costing information that your teams need.

With Frappe/ERPNext, the right BOM can support production planning, work orders and material requirements. The setup depends on your factory, item masters, stock process and people who maintain the information.

What we help with:

Organising product items and BOM structures.
Setting up sub-assemblies and relevant operations.
Reviewing cost sources, units and planning quantities.
Connecting BOM records to appropriate manufacturing and purchasing processes.
Training the team and improving the workflow where needed.

We assess version, configuration and customization needs before confirming individual features.

A BOM Is the Starting Point for Other Work

Manufacturing Management
See the complete factory journey from materials to finished goods.
Production Planning & Tracking
Understand how product requirements become part of a workable production plan.
Work Orders & Job Cards
See how planned manufacturing work is assigned and recorded.
Purchase Management
Understand how material needs continue into the purchasing process.
Quality Control & Inspections
See how materials and finished products are checked against the criteria your team defines.
Inventory Management
See why reliable stock records matter when checking material availability.

Which Product Is Hardest to Plan or Cost Correctly?

Tell us about a product, a changing material list or a costing problem in your factory. We will review where a clearer BOM and connected process could help.

Start My Business Audit Talk to Us

You do not need a finished ERP plan. Start with the product or process that is causing the problem.

Frequently Asked Questions

What is a Bill of Materials (BOM) in manufacturing?

A BOM is the list of materials and smaller assemblies needed to make a product, with their required quantities. It can also include the operations used to manufacture that product.

Can a BOM show the parts inside another assembly?

Yes. A multi-level BOM can show smaller assemblies such as a cabinet door, along with the raw materials needed to make them.

How does a BOM help when we produce 100 units instead of 10?

It gives a consistent starting point for scaling required material quantities. Actual purchasing needs also depend on available stock, incoming materials and the way production is planned.

Does ERPNext calculate estimated manufacturing costs from a BOM?

ERPNext supports BOM costing using configured material cost sources and operation costs. The result is an estimate and depends on the quality of the rates and records.

Can we include cutting, assembly or other operations in a BOM?

Yes. ERPNext BOMs can include relevant operations, times and workstation rates. The exact setup should match how your factory records work.

What if a material price changes?

The estimated BOM cost may need to be updated using the relevant cost basis and ERPNext settings. It is not the same as automatically changing a supplier's quotation or a completed job's actual cost.

Can we keep different BOMs for product changes?

ERPNext supports BOM records and controlled amendments or revisions. Your team should confirm which approved version is correct for new production work.

Does a BOM automatically tell us how much material is in stock?

No. A BOM states what a product requires. Stock availability needs inventory records and the appropriate material-planning checks.

Is BOM costing the same as the actual cost of a completed job?

No. A BOM is a planned estimate. Actual manufacturing records can reflect different material consumption, operation time or additional costs.

Can a small manufacturer move from Excel BOMs to ERPNext?

Often, yes. A practical start is to clean up item names, units, quantities and a few important product BOMs before connecting more production and purchasing activities.