Just-in-time (JIT) manufacturing reduces inventory and WIP by producing only what’s needed, when it’s needed. It can lower storage costs, improve cash flow, and reduce waste—but it increases exposure to demand swings, supplier delays, and schedule instability. Use JIT when demand and supply are reliable; use a hybrid JIT approach with capacity-based scheduling when variability is high.Most manufacturing facilities are looking to lower the costs associated with their production in order to maximize their profits. Over time, many scheduling techniques have emerged as a way to help these manufacturing facilities meet their production goals and increase their efficiency.
Just-In-Time manufacturing was designed to help manufacturers reduce inventory-related costs by receiving materials and producing goods only when they are needed. Just-In-Time scheduling is used to accommodate last-minute changes to orders and prevent damage or spoilage of inventory by preventing jobs from starting too early.
Just-In-Time (JIT) manufacturing is a production strategy that aims to produce goods or services exactly when they are needed and in the quantities customers demand. The primary objective of Just-In-Time (JIT) is to minimize waste, reduce inventory levels, and increase efficiency in the production process. For a deeper explanation of how JIT reduces waste and variability in production, see this engineering overview of just-in-time manufacturing.
When the techniques are implemented, production facilities can align their raw material orders directly with their production schedules, so these items do not have to be stored for long periods. Just-In-Time production scheduling prevents jobs from being scheduled well before they are needed, which requires holding WIP items in inventory. JIT means your production operations start with just enough time to be completed by the need date, so your goods are produced to ship, not to be stored.
There are many benefits to Just-In-Time production, but its main goals are to increase production efficiency while reducing waste, ultimately lowering production costs and increasing profits. Research on JIT implementations shows significant improvements in cost, quality, and delivery performance when the supporting infrastructure is in place, as shown in this meta-analysis of JIT manufacturing performance. On the flip side, implementing JIT requires producers to accurately forecast demand to avoid material shortages.
Before implementing Just-In-Time strategies, it is essential to understand the advantages and disadvantages of the process.
The advantages of Just-In-Time (JIT) manufacturing include the following:
While there are many advantages to the Just-In-Time manufacturing methodology, there are also some drawbacks to it as well. Listed below are some of the disadvantages of Just-In-Time (JIT) manufacturing.
The disadvantages of Just-in-Time (JIT) Manufacturing include the following:
A software that can aid with Just-In-Time (JIT) manufacturing is PlanetTogether’s Advanced Planning and Scheduling software (APS).
PlanetTogether’s APS software will automatically schedule your production operations so that they start with just enough time to be completed by their needed dates. For example, if an operation has a work content of one hour, the Just-In-Time start date will be set to one hour before the operation’s need date.
Release rules can be applied to allow operations to schedule before their JIT start dates. Slack days provide some additional time between the end date of the operation and its need date to accommodate last-minute variations. The flexibility of PlanetTogether APS allows manufacturers to set different scheduling rules on different machines.
APS software has become a must for operations that are seeking to take their production to the next level and can easily aid with efficiency increase, inventory control, waste elimination, and cost reduction. PlanetTogether’s APS software will take your production facility to the next level and turn your shop floor into a goldmine.
The shift to PlanetTogether is saving us about 15% in inventory overhead and about 20% in overtime labor expenses. We're not building equipment to stock any longer - we're building to ship.
Advanced Planning and Scheduling Software has become a must for modern-day manufacturing operations as customer demand for greater product assortment, faster delivery, and downward cost pressures grow. These systems help planners save time while providing greater agility in updating ever-changing priorities, production schedules, and inventory plans. APS Systems can be quickly integrated with ERP/MRP software to fill gaps in these systems' planning and scheduling flexibility, accuracy, and efficiency.
With PlanetTogether APS you can:
The implementation of an Advanced Planning and Scheduling (APS) Software will take your manufacturing operations to the next level of production efficiency by taking advantage of the operational data you already possess in your ERP system. APS is a step in the right direction of efficiency and lean manufacturing production enhancement.
Leading manufacturers choose PlanetTogether's production scheduling software to maximize profitability. Improve lead times, optimize inventory, and gain a competitive edge.
Lean initiatives break down when schedules can’t keep up with real constraints—capacity limits, material availability, and sequence-dependent changeovers. In this short video, you’ll see how an Advanced Planning & Scheduling (APS) system supports lean execution by creating feasible, constraint-aware schedules that reduce expediting, stabilize the shop floor, and enable more just-in-time production.
What you’ll learn:
Who this is for:
Production planners, operations leaders, and continuous improvement teams evaluating software to operationalize lean scheduling.
1) What is the main goal of JIT manufacturing?
The main goal of just-in-time (JIT) manufacturing is to reduce waste tied up in inventory and work-in-process (WIP) by producing and replenishing materials only when they’re needed. Done well, JIT improves cash flow, frees floor space, and shortens lead times by keeping production closely aligned to real demand.
2) What are the biggest risks of JIT?
The biggest risks are stockouts and production stoppages when demand spikes or supply slips—because there’s less buffer inventory. JIT can also increase expediting costs, expose weaknesses in supplier reliability, and amplify disruption from quality issues, changeovers, or schedule instability if planning and execution aren’t tightly controlled.
3) Is JIT the same as lean manufacturing?
No. JIT is one method within lean focused on flow and timing—reducing inventory by replenishing only when needed. Lean manufacturing is broader, including continuous improvement, quality at the source, waste elimination, standardized work, and designing processes that consistently deliver value with minimal variation.
4) How can manufacturers reduce stockouts while using JIT?
Reduce stockouts by improving schedule feasibility and supply reliability: tighten demand signals, reduce lead-time variability, and run schedules that reflect real constraints (labor, machines, changeovers, material readiness). Many operations also use targeted buffers for high-risk components, set service-level rules for replenishment, and improve visibility into inventory/WIP so issues are caught early.
5) When should a manufacturer use a hybrid JIT approach instead of pure JIT?
Use a hybrid JIT approach when variability is unavoidable—such as volatile demand, long/unstable supplier lead times, single-sourced parts, or high consequence of a stockout. Keep JIT (pull/lean replenishment) for stable product families, and use selective buffers or different planning rules for high-variability items so you stay lean without risking line stoppages.
Lean improvements stall when schedules rely on manual workarounds, expediting, and disconnected spreadsheets. If you’re evaluating APS to reduce waste and improve flow, this eBook shows what “better scheduling” looks like in practice—so you can translate lean goals into repeatable day-to-day execution.
Ready to make JIT reliable under real-world constraints? Request a demo to see how APS uses your ERP data to build feasible, finite-capacity schedules—reducing stockouts, expediting, and schedule firefighting.