• Assembling Machine 2: 0.75 Speed
• Assembling Machine 3: 1.25 Speed
• Chemical Plant / Furnace: 1.0 or 2.0 Speed
How the Calculator Works
(Yield ÷ Recipe Time) × Machine Speed
Total Machines Needed:
Target Output Rate ÷ Items Per Second
Ingredient Feed Rate:
(Ingredient Qty ÷ Recipe Yield) × Target Output Rate
In Factorio, efficiency is everything. The factory must grow, but growing without mathematical precision leads to severe resource bottlenecks, empty conveyor belts, and massive power waste.
When you decide to scale up your production, whether it is smelting iron plates, crafting electronic circuits, or building utility science packs, you need to know exactly how many machines to place down to hit your target output.
Our free Factorio Calculator does the ratio math for you. Simply input your desired target (Items Per Minute or Items Per Second), enter the recipe details, and select your assembly machine type. The tool will instantly output the exact number of machines required, the actual output rate, and the exact feed rate required for your raw ingredients!
How to Use the Factorio Ratio Calculator
We built this tool to handle any recipe in the game, from the simplest early-game gears to highly complex late-game rocket parts.
- Set Your Target: Enter how many items you want to produce and select your timeframe (Per Minute or Per Second).
- Enter Recipe Details: Look at the in-game tooltip for the item you are crafting. Enter the “Crafting Time” (in seconds) and the “Yield” (how many items are produced per single craft).
- Select Machine Speed: Different machines operate at different speeds. Select Assembly Machine 1, 2, or 3. If you are using Modules, Beacons, Chemical Plants, or Furnaces, you can type your custom Crafting Speed multiplier directly into the box.
- Enter Ingredients (Optional): If you want to know exactly how many raw materials you need to feed your new factory block, enter the required quantities for up to 3 ingredients.
- Hit Calculate: The calculator will instantly tell you exactly how many machines to build.
The Factorio Formula
Why can’t you just trust the “Crafting Time” listed on the recipe?
The biggest hurdle for new Factorio players is understanding the difference between Recipe Time and Real Time. When a recipe says it takes “1 second” to craft, that is only true if the machine crafting it has a speed multiplier of exactly 1.0.
Most early game machines are much slower. An Assembling Machine 1 has a speed of 0.5. That means a 1-second recipe will actually take 2 real-world seconds to complete!
Here is the formula our calculator uses behind the scenes:
- Actual Crafts Per Second = (1 ÷ Recipe Time) × Machine Speed
- Actual Items Per Second = Actual Crafts Per Second × Recipe Yield
- Exact Machines Needed = Target Output Rate ÷ Actual Items Per Second
Frequently Asked Questions (FAQs)
What are the standard machine crafting speeds?
Assembling Machine 1 (Grey): 0.5 Speed
Assembling Machine 2 (Blue): 0.75 Speed
Assembling Machine 3 (Yellow): 1.25 Speed
Stone Furnace: 1.0 Speed
Steel / Electric Furnace: 2.0 Speed
Chemical Plant: 1.0 Speed
How do I account for Speed Modules or Beacons?
If you are using modules that alter the speed of your machines, the game will display the newly adjusted “Crafting Speed” directly on the right-hand panel when you click on the machine. Simply type that exact number into the “Speed Multiplier” box in our calculator!
Why does the calculator show “Exact Math” under the machines required?
You cannot build half of an assembling machine! If the math determines you need 4.2 machines to hit your target, the calculator will tell you to build 5 machines. The “Exact Math” readout is provided for advanced players who want to perfectly balance their belts using clocking or under-clocking techniques.
How does the Raw Material Feed Rate work?
If you tell the calculator that you want to produce 60 Electronic Circuits per minute, it will look at the ingredient quantities you entered. Since one circuit requires 3 copper cables and 1 iron plate, the calculator will output that you need a raw feed rate of 180 copper cables per minute and 60 iron plates per minute to keep the machines running without stalling.
Does this tool work with mods like Space Exploration or Krastorio?
Yes! Because you manually input the recipe time, yield, and machine speed, this calculator is 100% agnostic. It works perfectly with vanilla Factorio as well as any massive overhaul mods that change the base game’s recipes.