Management games · Recipe quantities

Production recipes in management games: count raw materials once

A finished product needs components, and those components need materials. Turn that tree into one purchase list without paying for the same branch twice.

By Inquory Editorial · Documentation-informed, fictional worked example · Published November 4, 2026

The short answer: choose what to buy and what to make before expanding recipes. Combine shared component needs, subtract usable stock at that component’s level, then round its remaining requirement up to whole batches. Expand only those batches into their ingredients. Stop at purchased items.

This original exercise uses invented furniture, recipes and stock. It is not an Inquory World recipe, a gameplay test or a universal production optimizer. It calculates quantities, not time, affordability or profit.

Fix the recipe and the make-or-buy boundary first

Our fictional order is 5 desks and 4 stools, with no finished goods already available. One assembly batch makes one desk from 2 panels and 1 brace; another makes one stool from 1 panel and 2 braces. We will make every missing panel and brace, and buy only missing boards.

One panel batch consumes 6 boards and produces 4 panels. One brace batch consumes 2 boards and produces 3 braces. Usable, unreserved stock is 3 panels, 2 braces and 5 boards. All items of a kind are interchangeable; all inputs are consumed. Output is fixed, batches are indivisible, and surplus can be shared between the two orders.

There are no other commitments or incoming deliveries. The chain has no loops, byproducts, probability, productivity bonuses, quality grades or alternative recipes. If your game has any of those, this simple calculation needs additional rules. Check the selected recipe rather than assuming an item always has one way to be made.

Combine shared needs before rounding batches

The desks require 10 panels and 5 braces; the stools require 4 panels and 8 braces. Together that is 14 panels and 13 braces. Subtract the existing 3 panels and 2 braces once, leaving 11 of each to make. Do not expand the panels and braces already on the shelf into new board purchases.

For a fixed batch, batches needed = round up(max(0, combined need − usable stock) ÷ output per batch). For panels, round up(11 ÷ 4) = 3 batches. For braces, round up(11 ÷ 3) = 4 batches. A fractional batch is not available under our rules.

Focus the table and scroll horizontally on a small screen. Check conservation after assembly: 3 + 12 − 14 = 1 panel; 2 + 12 − 13 = 1 brace; 5 + 21 − 26 = 0 boards. Both finished orders are covered, with one spare of each component.

Rounding each product separately can overstate shared production. In a separate small example with no stock, two jobs needing 1 panel each require two batches if rounded separately, but only one shared batch of 4. That leaves 2 spare panels rather than 6. Combine the needs before rounding when sharing is permitted; never allocate the same stock to both jobs.

A purchased component ends that branch

Suppose you instead buy all 11 missing panels individually while still making braces. Buy 11 panels and make 4 brace batches, consuming 8 boards. With 5 boards available, buy only 3 boards. Adding the panels’ hypothetical 18 boards as well would count a purchased component and its manufacturing inputs together.

This alternative is not automatically cheaper or faster. It merely changes the boundary of the purchase list. Compare actual supplier units, prices and availability separately. If purchases come in packs, apply the pack size at that purchasing boundary and track its surplus too.

Copy a recipe check

• Target: game/version ___; finished quantities ___; usable finished stock ___; selected recipes ___.
• Boundary: buy these items ___; make these items ___; stop expanding at each purchase ___.
• Each shared item: combined need ___; stock allocated once ___; net need ___; output per batch ___; rounded batches ___.
• Reconcile: batches × ingredient quantities ___; next level’s shared totals ___; purchases after stock ___; closing surplus ___.

Work from finished demand toward purchased inputs, processing an item only after all its upstream demands are combined. A quantity list does not establish when materials arrive: use the inventory timing ledger for that. Check production rates, worker eligibility and payment timing separately.

What the primary documentation supports

Wube’s historical Factorio Friday Facts #397, February 9, 2024, describes following ingredient recipes and discovering recipes that use an item; it also describes displaying alternative recipes. That supports checking relationships and recipe choice, not our invented furniture quantities.

Friday Facts #426, August 30, 2024, distinguishes recipe information from a particular output item and discusses speed and productivity modifiers. These dated developer descriptions explain why a recipe and its output are different things. They do not validate this simplified ledger for every Factorio configuration or another game.