The short answer
Production planning decides the quantities and dates — what to make and buy, and how much — while production scheduling decides the sequence — when each job runs, in what order, and on which machine. Planning is the MRP question; scheduling is the shop-floor-control question. They are different jobs on the same chain: planning produces work orders, scheduling arranges them onto real machines and days. A complete system does both, and doing only one leaves a predictable gap. For the whole model, see the production planning pillar.
What production planning does
Planning is the domain of MRP. It takes demand, explodes each finished good through its bill of materials, nets the requirements against stock and open supply, and splits the shortfall into purchase requisitions to buy and work orders to make. Its output is a set of quantities and target dates: make 50 housings, buy nothing on gears, send 100 shafts out for grinding. Planning is periodic and demand-driven, and it deliberately treats capacity as available — it decides what should happen before worrying about whether every machine-hour lines up. See what is MRP and the planning process.
What production scheduling does
Scheduling is the domain of shop-floor control. It takes the work orders planning released and arranges them: sets a priority for each (by due date, customer, or setup similarity), loads their operations onto machines against the hours those machines actually have, and lays the whole lot out on a Gantt board where a planner can drag to re-sequence. Scheduling is live — this week, this shift, this machine — and it respects finite capacity, because its job is to make the plan runnable on the resources that exist. See scheduling & priority (Gantt).
Planning vs scheduling, side by side
| Aspect | Production planning (MRP) | Production scheduling (control) |
|---|---|---|
| Answers | What to make and buy, and how much? | When, in what order, on which machine? |
| Works on | Demand, BOM, stock, open supply | Work orders, operations, machine capacity |
| Output | Purchase requisitions & work orders | A sequenced, loaded schedule |
| Capacity | Assumed / infinite | Finite — respects available machine hours |
| Horizon | The planning period — the month, the run | Live — this week, this shift, this machine |
| Driven by | Demand and the BOM | Priority rules and capacity |
| Complete when | Together — planning sets the quantities, scheduling makes them runnable; neither alone runs a plant | |
Finite versus infinite capacity
The distinction that trips buyers up sits right at the boundary between the two. Infinite loading assumes a machine can absorb any amount of work — which is fine for the rough, capacity-blind view MRP takes to get quantities right. Finite loading respects each machine’s available hours and refuses to load more, so an overload surfaces as a loading percentage above 100% instead of a silent promise the floor cannot keep. Scheduling is where finite loading lives, and it is what converts MRP’s infinite-capacity suggestions into a week the shop can actually run.
- Planning can suggest 500 pieces this week whether or not the machine has the hours — that is by design.
- Scheduling checks those hours and shows the overload before the week starts.
- % loading over 100% is the signal to re-sequence, move work, or add a shift.
- Projected availability tells you when a busy machine is next free, so promised dates are realistic.
See machine loading & capacity for how load and capacity are compared.
Where planning hands off to scheduling
The hand-off is the work order. Planning’s last act is to generate work orders (with routings) and purchase requisitions from the netted plan; scheduling’s first act is to take those work orders, prioritise them, and load them onto machines. On a shared platform the hand-off is seamless because there is nothing to hand — the same work-order records planning created are the ones scheduling sequences, on one engine reading one set of tables. On disconnected systems, that boundary is where a plan and a schedule quietly diverge.
Picture the boundary in practice. Planning nets a week of orders and releases twelve work orders — the quantities are right, the material is covered, the due dates are set. That is where planning stops. Scheduling now asks a different question of the same twelve orders: which runs first on the shared turning centre, which can wait, and does any machine tip over 100% loading once every operation is laid on the timeline? It might re-sequence three orders by due date and shift one to a second machine to level the load. Nothing about the quantities changed — only the sequence — yet without that second pass the correct quantities would still have missed a date. That is why the two steps are distinct jobs that only add up as a chain.
Want to see the planning-to-scheduling hand-off live?
We’ll run MRP on your BOM to generate work orders, then load and sequence them on a finite-capacity Gantt board — so you can watch quantities become a runnable schedule in one system.
The cost of confusing them
Treating the two as one thing is expensive in both directions. A shop that only plans gets correct quantities and target dates but no sequence, so the floor decides order by feel and the bottleneck machine is discovered when a job is already late. A shop that only schedules sequences beautifully but against quantities that were never netted — so it runs work for material it does not have, or builds what it already holds. The value is in the chain: plan to get the numbers right, schedule to make them runnable, and keep both on the same data so the schedule always reflects the latest plan.
There is a subtler cost too. When planning and scheduling live in separate tools, a mid-week change — a rushed order, a machine breakdown, a revised due date — has to be entered twice and reconciled by hand, and the version the floor is working to drifts from the version the planner believes is current. Keeping both on one engine means a re-plan immediately re-sequences, and a re-sequence never contradicts the netted quantities. The distinction between the two jobs is worth understanding precisely because a good system lets them act as one continuous chain rather than two documents someone has to keep in step.
How Fast Planning does both
Fast Planning Software, built by Improsys in Pune under the Fast Technology brand, holds planning and scheduling on one shared platform. The MRP engine explodes the BOM and nets to produce work orders and purchase requisitions; finite machine loading and order-priority Gantt scheduling (on a DayPilot board) sequence those work orders against real capacity. Because both read the same tables, the schedule always reflects the latest plan, and completion booked on the floor flows back to plan-vs-actual and OEE — no interface to production, inventory and purchase. To see where each fits in the full cycle, read the production planning process.
Frequently asked questions
What is the difference between production planning and production scheduling?
Production planning decides quantities and dates — what to make and buy and how much — by exploding the BOM and netting demand against stock and supply (the MRP job). Production scheduling decides sequence — when each job runs, in what order and on which machine — by prioritising released work orders and loading them against finite capacity (the control job). Planning assumes capacity to get quantities right; scheduling respects capacity to make them runnable.
Is MRP the same as scheduling?
No. MRP is production planning: it explodes the BOM, nets against stock and open supply, and raises purchase requisitions and work orders, treating capacity as available. Scheduling is the separate step that takes those work orders and sequences them onto machines and days against finite capacity, usually on a Gantt board. A complete system does both, so MRP’s quantities are actually loadable on the machines you have.
What is finite versus infinite capacity scheduling?
Infinite scheduling assumes a machine can absorb any amount of work — acceptable for MRP’s rough, capacity-blind planning view. Finite scheduling respects each machine’s available hours and refuses to load more, so overloads surface as a loading percentage above 100% rather than a silent promise the floor cannot keep. Finite loading lives in the scheduling step and turns capacity-blind suggestions into a runnable week.
Which comes first, planning or scheduling?
Planning comes first. It decides what work orders should exist and in what quantities by netting demand against supply. Scheduling then takes those released work orders and sequences them onto machines and days. The hand-off point is the work order: planning’s last act generates it, scheduling’s first act sequences it. On one platform the two share the same records, so the schedule always reflects the latest plan.
What happens if you plan but don’t schedule?
You get correct quantities and target dates but no sequence, so the floor decides order by feel and discovers the bottleneck machine only when a job is already late. The reverse is just as costly: scheduling without planning sequences work against quantities that were never netted, so you run jobs for material you don’t have or build what you already hold. The value is in doing both on the same data.