How to Plan Materials with MRP in Catalystk
MRP (material requirement planning) tells you exactly what raw materials to buy for production. In Catalystk's free MRP software you pick the bill of materials and the quantity to make, explode the BOM and calculate – and see the gross requirement, available stock and net requirement, with every material shortage marked Short. Then convert the plan into a purchase request or work order, or load it into a purchase order by MRP No.. Print the MRP plan as PDF free – MRP never moves stock, so you can plan safely.
- Explode BOM
- Gross / net
- Shortages
- Plan PDF
- Free
Before you start: create the bill of materials for the product you plan to make.
Open Mrp and click New MRP
Every material plan starts from the MRP list.
- 1
Go to Manufacture → Mrp
In the left menu, open Manufacture and click Mrp, then New MRP.
- 2
Choose the BOM and quantity
Search the BOM Code or BOM Name, then enter the No of Lots. In Demand, add the Required Quantity, Required Date and Demand Source, and save.
Explode the BOM and calculate
Two buttons turn the BOM into a list of materials to buy.
- 3
Click Explode BOM
Click Explode BOM to bring in every component of the BOM, including sub-assemblies.
- 4
Click Calculate
Click Calculate. Catalystk checks the stock and works out the gross and net requirement for each material.
Read gross, available and net requirement
The plan shows exactly what is short.
- 5
Check each material
Each line shows Per Quantity, Gross, Available and Net Quantity. A Short badge means the net need is more than what is available.
- 6
Firm the plan
When the plan is right, click Firm Plan. The plan moves from Planned to Firmed.
Buy the shortages
Turn the plan into a purchase request, work order or purchase order.
- 7
Convert the plan
On a firmed plan, click Convert to create a purchase request for the net quantity, or a work order to make it.
- 8
Or load it into a purchase order
In a new purchase order, type the plan number in MRP No. to load the items. Click Print Plan for a PDF of the MRP plan.
Gross vs available vs net requirement
Three numbers tell you what to buy.
| Figure | Meaning |
|---|---|
| Gross | Total quantity of the material needed for the planned production |
| Available | Stock you already have |
| Net | What is still needed after using available stock |
| Short | Shown when the net need is more than what is available – buy or make it |
A plan moves through Planned → Firmed → Converted → Closed. MRP never moves stock – it only plans.
Tips for MRP planning
- Keep stock up to date before you calculate – MRP uses your current stock.
- Add waste % in the BOM so MRP plans enough material.
- Firm the plan only when the quantities are final, then convert it.
- Print the plan as PDF for your purchase team.
Frequently asked questions
What is MRP (material requirement planning)?
MRP works out which raw materials, and how much of each, you must buy or make to meet planned production.
What does Explode BOM do?
It brings every component of the BOM, including sub-assemblies, into the MRP plan.
What do gross, available and net mean?
Gross is the total need, available is the stock on hand, and net is what is still needed. Short marks materials you must buy or make.
Can MRP create purchase requests or work orders?
Yes. Convert a firmed plan into a purchase request or a work order, or load it into a purchase order with the MRP No. search.
Does MRP change my stock?
No. MRP only plans – stock moves only when you receive or issue materials.
Can I print or download the MRP plan?
Yes. Click Print Plan to get the MRP plan as a PDF.
Is the MRP software free?
Yes. MRP is part of Catalystk's free plan – free online, nothing to download.
What's next: start production – create a work order from a BOM.
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