The common answer is 8 beacons per electric furnace for a compact, high- efficiency smelting block in Factorio, with 12 beacons also used in some older or space-heavy layouts. The best choice depends on whether you care more about space efficiency, simplicity, or raw throughput.

What players usually use

  • 8 beacons : very common for modern smelting setups and generally the best all-around choice.
  • 12 beacons : sometimes used for special high-density layouts or older blueprints, but it is less space-efficient in many cases.
  • Fewer beacons : workable early on, but usually not the “best” beacons-per-furnace ratio once you are optimizing.

Practical take

If you just want a solid answer for a blueprint, start with 8 beacons around the furnace block. That is the setup most players point to as the sweet spot for electric furnace smelting.

Why the answer varies

Different layouts trade off:

  • Space usage.
  • Module choices.
  • UPS/performance.
  • How cleanly belts and inserters fit.

So there is not one universal “maximum” that is always best; it is more about which design goal you want.

TL;DR

For most Factorio electric furnace builds, use 8 beacons per furnace setup. If you are copying a very dense or older design, 12 beacons can also appear, but 8 is the safer default.