Key Concepts
Before you dive into Partsemble, it helps to understand a few core ideas. These concepts show up throughout the app and in our documentation.
Products
A product is anything you track inventory for in Partsemble. Every product has a SKU, a name, a stock quantity, and a unit cost. Products come in four types:
Raw material — purchased ingredients or materials that you don't manufacture. Flour, screws, essential oils, resistors. These are the inputs to your production process.
Component — a part or intermediate item used in assembly. Sometimes purchased, sometimes produced in-house. The distinction from raw materials is organizational — use whichever label fits how you think about your inventory.
Sub-assembly — a product that is itself built from components and then used as a component in another product. A circuit board that goes into a larger device, or a sauce base that goes into multiple finished products.
Finished good — the end product you sell. This is what your BOMs produce.
You don't need to use all four types. Many businesses only use raw materials and finished goods. Use what makes sense for your operation.
Bills of Materials (BOMs)
A bill of materials is a recipe. It defines what goes into a product: which components, how much of each, and any additional costs like labor or overhead.
Each BOM belongs to a single product and has a version number. You can have multiple BOM versions for the same product (for example, v1 and v2 of a formula), but only one can be active at a time. The active BOM is what Partsemble uses when you execute a build.
BOMs can include optional components — items that are sometimes included but shouldn't block a build if they're out of stock. They can also include cost lines for non-inventory expenses like labor, packaging, or machine time.
Builds
A build is the act of manufacturing. When you execute a build, Partsemble consumes the component quantities defined in the BOM, produces the finished good, calculates the total cost, and records the transaction.
There are two ways to build:
Quick build — select a product and quantity, confirm the component consumption, and execute immediately. Best for simple, routine production.
Planned build — schedule a build for a future date, optionally assign it to a team member, and add it to the build queue. Execute it when you're ready. Best for production planning and team coordination.
Builds flow through a lifecycle: Planned → Executed → (optionally) QA Approved → Exported to accounting. Each step is tracked with timestamps and the user who performed it.
Build Queue
The build queue is your production schedule. It shows all planned builds in priority order, and you can drag to reorder them. Each planned build shows the product, quantity, target date, assigned team member, and whether you have enough components in stock.
Stock and Costs
Partsemble tracks stock on hand for every product. When you execute a build, component stock goes down and finished good stock goes up. When you receive inventory, stock goes up. When a sale is recorded, stock goes down.
Costs are calculated using weighted average costing. When you receive new inventory at a different price, the unit cost adjusts. When you build, the finished good's cost is the sum of all consumed components (at their current weighted average cost) plus any cost lines on the BOM.
Reorder Points and Build Points
A reorder point is the stock level at which Partsemble shows a low-stock alert on your dashboard. Set this on any product to get notified before you run out.
A build point works similarly but for finished goods. When stock falls below the build point, Partsemble suggests a build (or auto-creates a planned build) to bring stock back up to the target level. This is useful for staple products you always want in stock.
Accounting Export
After a build is executed (and QA-approved, if you use QA review), it can be exported to your accounting system. The export creates the appropriate transactions: inventory adjustments for component consumption and finished good production, plus a journal entry for COGS if applicable.
Export can be automatic or manual, depending on your settings. Failed exports can be retried, and you can see the sync status of every build.
Tiers and Features
Partsemble has three plans — Maker, Pro, and Advanced — each unlocking additional features. Some features mentioned in this article (like QA review, receiving, sales tracking, and team management) are only available on higher tiers. See Choosing a Plan for a full comparison.
During your 14-day free trial, all features are unlocked so you can explore the full product before deciding on a plan.