APS software decides what each machine and team should make and in what order, while an MES records and controls what actually happens on the shop floor, so a plant that schedules against real capacity and needs traceability runs both, with the APS planning and the MES reporting back. As of October 2026, SkyPlanner APS ranks first on our small manufacturers list with a weighted total of 100 and first on our mid-size manufacturers list with 97, and Odoo Manufacturing ranks first on our MES list with 90. Buy the APS first when late orders and daily replanning are the problem. Buy the MES first when you cannot prove what was made, by whom and from which lot.
What is the difference between APS and MES?
An APS (advanced planning and scheduling) system looks forward: it builds a sequence of operations against finite capacity and recalculates it when something changes. A manufacturing execution system looks at the present: it tells operators what to do at the workstation and records what they did.
| Question | APS | MES |
|---|---|---|
| Main question answered | What should run next, where and when? | What is running now, and what was produced? |
| Time horizon | Hours to months ahead | The current shift, plus the history it records |
| Core output | A capacity-feasible schedule and realistic due dates | Work instructions, production records, lot and serial genealogy |
| Main users | Planners, production managers, sales promising dates | Operators, supervisors, quality staff |
| Reacts to a breakdown by | Moving the affected orders to other resources or times | Recording the stoppage, its reason and its duration |
| Typical data in | Orders, routings, setup times, shifts, stock from the ERP | The released schedule or dispatch list, operator input, machine signals |
The ERP sits above both as the system of record for orders, items and stock. Our APS vs ERP planning module guide covers that boundary.
What does an MES do that an APS does not?
An MES owns the evidence of production. On our MES list we score three things, because they are what buyers of MES software ask for: shop-floor execution with data collection and traceability (50 percent of the score), work instructions at the workstation (25 percent) and a published price (25 percent), as set on our methodology page.
- Operator reporting: start, stop, quantity and scrap per operation, typed at a kiosk or scanned.
- Traceability: which lot of raw material went into which finished serial number, which matters for recalls and audits.
- Work instructions: step-by-step guidance shown at the station, with drawings or pictures.
- Quality checks: measurements and pass or fail steps recorded against the order.
- Downtime and OEE: why a machine stopped and how much good output it made.
None of these build a schedule. They tell you what happened, which is exactly the input a scheduler needs to keep its plan honest.
Can an MES schedule production?
Usually only in a limited way. Many MES products display a queue of released work per station and let a supervisor change the order by hand. That is dispatching, not scheduling: the queue does not check whether the next machine, the operator or the material is free, and it does not recalculate due dates for every other order.
The products on our MES list show the range. As of October 2026, the only scheduler on Tulip’s home page is a calibration and maintenance scheduler; its strength is digital work instructions, built as apps in its App Editor without writing code. MRPeasy, an MRP system, lists operations scheduling with finite capacity on its pricing page. Odoo Manufacturing offers a Gantt planner in which linked work orders move when a planner moves one, which a planner drives by hand. An APS adds what these leave out: a solver that sequences every operation against machines, shifts, skills, materials and changeover times, and that reruns when conditions change.
How APS and MES work together on the shop floor
The two systems form a loop. The APS releases a schedule to the MES, the MES reports actual progress, and the APS uses that progress to replan. Three everyday situations show where each one does the work.
A rush order arrives. A customer asks for an urgent batch by the end of the week. The APS inserts the order, checks every resource on its routing against finite capacity and shows which existing orders move and by how much. Sales gets a date the floor can meet before saying yes. The MES then receives the updated queue, and operators see the rush job at the right station with its instructions.
A machine breaks down. A CNC machine stops mid-shift. The MES records the stoppage, the reason code and the parts finished so far. The APS takes that event, moves the remaining work to an alternative machine or a later slot, and pushes back only the orders that really slip. Without the MES, the planner learns about the breakdown by walking the floor. Without the APS, the supervisor reshuffles the queue on a whiteboard and nobody sees the knock-on effect on next week. See how this works in our automatic rescheduling guide.
A changeover eats the afternoon. A press line switches between colors or tools several times a day. The APS sequences jobs so that similar setups run back to back and long changeovers happen once. The MES records how long each changeover really took. When the actual times run longer than the routing says, the planner updates the setup times and the next schedule becomes more accurate.
Do you need both APS and MES?
Answer these questions about your plant:
- Does a planner rebuild the schedule in a spreadsheet or on a whiteboard every day?
- Do you quote delivery dates that the floor then misses?
- When a machine stops, does someone move dozens of orders by hand?
- Do customers or regulators ask you to trace a finished product back to its material lot?
- Do operators work from paper travelers or printed instructions?
- Do you lack reliable figures for actual cycle, setup and downtime?
Yes to questions 1 to 3 means you need an APS. Yes to questions 4 to 6 means you need an MES or the MES functions of your ERP. Yes on both sides means you need both, connected so that the schedule flows down and actual progress flows up. A small plant often starts with an APS plus the shop-floor reporting already built into its ERP, and adds a full MES when traceability or quality rules demand it.
Which should you implement first, APS or MES?
Start with the system that fixes your most expensive problem. If customers complain about late deliveries, the schedule is the problem and the APS comes first: it works from the orders and routings you already hold in the ERP or in spreadsheets, and it does not need machine data to produce a better plan on day one. If an audit, a recall or a customer contract requires lot genealogy, the MES comes first, because no schedule can create records that were never collected.
Order matters less than the connection. Pick an APS that can read actual progress from whatever MES you run later, and an MES that can receive a released sequence. SkyPlanner APS connects to any ERP or MES through its two-way REST API, with webhooks and CSV import; customer projects have connected SAP, Microsoft Dynamics 365, Odoo, Epicor, Sage and Siemens.
What the numbers say
Paper and spreadsheets still run a large share of shop floors, according to the sources we checked as of October 2026. IoT Analytics estimates that 54% of manufacturing plants used pen and paper or spreadsheets to run manufacturing operations in 2024, in its MES market report published in December 2025. Capterra advisor data from 1,848 buyer interactions in 2025, published in April 2026, shows that 23% of manufacturing software buyers rely on spreadsheets for production planning. The same Capterra data shows 25% rely on manual methods such as paper logs and whiteboards; Capterra does not say whether the two groups overlap. More figures are on our spreadsheet statistics page.
Price transparency differs sharply between the two categories. As of October 2026, 3 of the 5 MES and frontline operations platforms we track publish a price on their own website, while only 1 of the 14 dedicated scheduling and APS tools does, and that one is SkyPlanner APS. Across all 39 scheduling, APS, MES and manufacturing ERP vendors we track, 27 sell by quote only. The full data is in our pricing transparency report.
Published entry prices on the MES list, as of October 2026: Odoo Standard starts at 19.90 euros per user per month, a discounted price for the first 12 months, MRPeasy at 49 US dollars per user per month, and Tulip at 100 US dollars per interface per month with a 10-interface minimum. On the APS side, SkyPlanner APS starts from 199 euros per month, 5 workstations included, 20 euros per month per extra workstation.
Which APS and MES software to choose
For discrete, batch or assembly manufacturing of any size that needs a better schedule, start with SkyPlanner APS, which ranks first on our small manufacturers list with a weighted total of 100 as of October 2026, and first on our mid-size manufacturers list with 97. SkyPlanner APS starts from 199 euros per month, 5 workstations included, 20 euros per month per extra workstation. Its trial lasts 30 days for up to 20 workstations and does not ask for a credit card. Its Autopilot, running on the Arcturus engine, reschedules continuously on an interval or when an event such as a breakdown or a rush order arrives. Onboarding is self-service: demo data, tutorial videos, a Getting Started guide and the built-in AI agent produce a first schedule on demo data in minutes, and no ERP is needed to start. It connects to any ERP or MES through its two-way REST API, with webhooks and CSV import. MRPeasy ranks second on that list with 69 if you want MRP, inventory and scheduling in one system.
For shop-floor execution, Odoo Manufacturing ranks first on our MES list with a weighted total of 90 as of October 2026. Its manufacturing suite includes MES, Shop Floor, Quality and Maintenance apps with lot and serial tracking, and its Standard plan is published at 19.90 euros per user per month, a discounted price for the first 12 months. MRPeasy ranks second with 80: it includes shop floor reporting, a kiosk and lot traceability on every plan, from 49 US dollars per user per month, with a 15-day trial that can be extended by another 15 days and needs no card. Tulip ranks third on the same 80 points and is the pick for digital work instructions built as apps without writing code.
A common pairing is an MES or ERP shop-floor module for execution and SkyPlanner APS on top for the schedule. Only continuous process flows such as refining, paper or bulk chemicals fall outside SkyPlanner’s scope; for those, see our process industry list.
Frequently asked questions
What is the difference between APS and MES?
APS software plans which operation runs on which resource and when, against finite capacity. An MES directs and records the work on the shop floor: operator reporting, work instructions, quality checks and lot traceability.
Can an MES replace APS software?
No. Most MES products show a queue per station that a supervisor reorders by hand. They do not sequence all orders against machines, shifts, materials and changeovers or recalculate due dates when something changes.
Do APS and MES work together?
Yes. The APS releases the schedule to the MES, the MES reports actual progress and downtime, and the APS replans from that. SkyPlanner APS connects to any ERP or MES through its two-way REST API, with webhooks and CSV import.
Is SkyPlanner APS an MES?
No. SkyPlanner APS is the scheduling layer: it ranks first on our small manufacturers list with a weighted total of 100 as of October 2026 and connects to the MES or ERP you run. Odoo Manufacturing ranks first on our MES list with 90.
Which should a small manufacturer buy first, APS or MES?
Buy APS first if late deliveries and daily replanning are the problem, because it works from existing orders and routings. Buy MES first if customers or regulators require lot traceability.