What is MRP, and do you actually need it?
MRP stands for Material Requirements Planning. It answers three practical questions: what materials do I need? How many do I need? When do I need them?
To answer them, an MRP system combines four things:
- what the business expects or has committed to make;
- the bill of materials, recipe or formula for each product;
- materials already on hand, or already ordered and on their way;
- supplier and production lead times.
It then calculates the shortages and recommends what to buy or make, in what quantity, and by what date. That last part. The date, is what separates it from everything else in this market.
The difference, in one example
An inventory app says
“You have 18 pounds of wax left.”
True, useful, and entirely about today. You still have to work out what that means.
A true MRP system says
“Order 80 pounds of wax by Friday, because the supplier needs twelve days and two production batches must start the following week.”
A decision, with a deadline. That is the whole value.
How we decide what counts
A great many products use the letters MRP without doing this calculation. Rather than argue about it, we apply six tests, identically, to every product. All six must pass, and every capability the tests rely on must be backed by a first-party page we link to.
- 1It represents a bill of materials, recipe, or formula.
- 2It accepts dated demand, sales orders, a forecast, or a master production schedule.
- 3It nets that demand against stock on hand and orders already incoming.
- 4It explodes requirements through at least one level of the bill of materials.
- 5It uses lead times or required dates.
- 6It produces dated buy, make, transfer, release, or reschedule recommendations.
Why so few products qualify
Of the 139 products in this directory, 28 currently pass all six tests, whatever class they carry. That is not because the others are bad, most are good at what they do. It is because rules five and six, lead-time offsetting and dated recommendations, are the hardest to find first-party evidence for, and we will not award the label without it.
Where a product falls short only because we have not found the documentation, we say so on its page and list exactly what evidence we are looking for.
Which one do you need?
Answer honestly. Most small shops do not need full MRP, and that is fine.
You probably need recipes and inventory, not MRP, if…
- · Your suppliers deliver in days, not weeks.
- · You make to stock and sell from the shelf.
- · You rarely get caught out by a stockout.
- · Your main problem is knowing what things cost, not when to order them.
You probably do need real planning if…
- · You commit to customer orders with dates you must hit.
- · Some of your materials take weeks or months to arrive.
- · You have been caught short on something you should have ordered a month earlier.
- · One missing component stops a whole build.
The kinds of product you will run into
Seven categories, because calling them all MRP helps nobody.
- Full MRP6 products
- Verified to take dated demand, net it against stock and incoming orders, explode a bill of materials, apply lead times, and produce dated buy-or-make recommendations.
- Manufacturing ERP56 products
- A broad business system (accounting, sales, purchasing) with a substantial manufacturing or planning module attached.
- Batch / process manufacturing26 products
- Built around recipes or formulas, batch runs, and lot genealogy. May or may not include full time-phased planning.
- Light manufacturing38 products
- Has bills of materials or recipes, consumes stock when you build, and tracks production, but time-phased planning is not verified.
- BOM & inventory8 products
- Tracks product structure, parts, costs, and purchasing without a complete plan-and-execute production loop.
- Planning / APS3 products
- A forecasting, constraint-planning, or scheduling engine that normally sits on top of another system that holds your transactions.
- MES / shop floor2 products
- Runs and records what happens on the floor. Execution, not planning, usually downstream of an ERP or MRP system.
One more acronym worth separating
MRP plans materials for manufacturing. MCP usually means Model Context Protocol in modern software: an open standard that lets AI applications connect to outside data and tools. MCP support may help an AI assistant read or act on your manufacturing data, but it does not make a product an MRP system. We record it as an integration field, and 15 products in this directory have it.
The full glossary is here if a vendor uses a word you would rather look up before the call than during it.
Ready to narrow it down?
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