Production planning is the part of manufacturing that decides what gets made, when, and with what. Most manufacturers do it on spreadsheets and in the heads of a few experienced people, and most manufacturers feel the strain of doing it that way. This guide explains what production planning software is, what it does, how planning relates to scheduling, and how a manufacturer should think about adopting it.
What production planning software does
Production planning software answers a deceptively hard question: given the orders we have, the stock we hold, the materials we can get, and the capacity we run, what should we make and when? Doing that well means holding several moving things in view at once. Demand changes. Stock changes. Supplier lead times vary. Machines and people have limits. A spreadsheet can hold a snapshot of all that, but it cannot keep the snapshot current, and the moment one input changes the plan is quietly wrong.
Production planning software keeps the plan connected to its inputs. When an order arrives, a delivery slips, or a machine goes down, the software can recalculate what that means for the plan instead of leaving someone to work it out by hand. The plan stops being a document and becomes a live answer.
Planning versus scheduling
The terms planning and scheduling are used loosely, and the difference is worth being precise about. Planning works at the higher level and the longer horizon: over the coming weeks, what should be produced, in what quantities, and is there enough material and capacity in principle to do it. Scheduling works at the detailed, near-term level: of the work that planning has approved, exactly which job runs on which machine, in which order, starting when. Planning decides what and roughly when; scheduling decides the precise sequence on the floor. Good production planning software does both, and keeps them consistent, so a scheduling change does not silently break the plan above it.
What it connects to
Production planning is not an isolated function. A plan depends on demand, which comes from sales orders and forecasts. It depends on stock, which comes from inventory. It produces purchasing requirements, which go to procurement. It commits capacity, which is the shop floor. This is why production planning is rarely bought as a standalone tool and is usually a capability inside a manufacturing ERP, where the demand, stock, purchasing, and capacity it depends on already live in one model. Planning software that is disconnected from those inputs spends its life being fed data by hand, which reintroduces the very problem it was meant to solve.
The role of MRP
At the centre of most production planning software is MRP, material requirements planning. MRP takes demand, explodes it through the bill of materials to work out every component required, compares that against stock on hand and supply already incoming, and produces the list of what to make and what to buy and by when. MRP is the calculation engine of production planning. The software wraps that engine in the inputs it needs and the plan it produces. A later piece in this series covers MRP in its own right.
The honest condition: the data underneath
Production planning software is only as good as the data it plans from. If bills of materials are inaccurate, lead times are guesses, or stock figures are wrong, the software will calculate a confident plan from bad inputs and the plan will be wrong with conviction. This is the single most common reason planning software disappoints. The remedy is not better software, it is accurate master data, BOMs, lead times, and stock that reflect reality. A manufacturer adopting planning software should expect to spend real effort getting that data right, because the software cannot.
What a manufacturer gains
When the data is sound, the gains are concrete. Material shortages are seen in advance instead of when the line stops. Capacity problems surface while there is time to react. The plan reflects the current situation rather than last week's. The knowledge of how to plan stops living only in a few heads and starts living in a system. And the plan becomes something the whole business can see and trust, rather than a spreadsheet only its author understands.
How to approach adopting it
A manufacturer should treat production planning software as part of its manufacturing ERP rather than a separate purchase, invest first in the master data the plan depends on, and roll out planning after the basic operating flow is steady, because MRP only plans well on top of reliable BOMs and stock. Approached that way, production planning software moves a manufacturer from reacting to shortages to anticipating them. For how we approach manufacturing systems, see our manufacturing work.