Spawn-Proofing by Arithmetic

Verified: Java 26.3 / Bedrock 26.50 · 2026-09-16 · Updated 2026-09-16

Torch spacing is one subtraction and one map metric, yet the folk numbers — every 12, every 8, "just spam them" — mostly date from a rule the game retired years ago. This guide derives the current numbers the torch spacing calculator reports, so you can check them on graph paper.

The model: light as taxicab distance

Block light drops by exactly one level per block of taxicab distance — steps counted along the grid, where a diagonal is two steps, not one. A torch emits 14, so the floor one block away holds 13, and a block d steps away holds 14 − d until the light runs out at 14 steps. The bright diamond around a torch that every player recognizes is this metric drawn literally: contours of equal taxicab distance are diamonds, not circles. That single fact is the whole model, and it is what the calculator and its test suite simulate.

The rule change that halved your torch bill twice

Before 1.18, hostile mobs could spawn at light 7 or below; safe ground needed light 8 or more. Since the 1.18 light rework — mirrored in Bedrock's 1.18.0 line — overworld hostiles need block light exactly 0. One level of torchlight now shuts spawning down. The safe reach of a torch went from 6 blocks (14 − 8) to 13 blocks (light 1 survives at distance 13), which more than quadruples the area each torch protects. Sky light does not rescue you at night, and moonlight stops nothing: after dark, only block light counts, which is why the surface lights up with spawns the moment the sun sets on unlit ground.

Deriving the three spacings

Call the safe reach R — for a torch under the current rule, R = 13. In a corridor, the worst block sits midway between two torches, so the spacing can be 2R + 1 = 27: the midpoint block is 13 from each side and holds light 1. In an open field on a square grid of spacing s, the worst block sits half a spacing off along both axes, a taxicab distance of twice the floor of s/2 — which is s itself when s is even but only s − 1 when s is odd, because the diamond of light tiles better on odd spacings. The rule that falls out: the grid can be as wide as R when R is odd (torch: 13), and R + 1 when R is even (lantern: 15, and the legacy torch's 6 reach actually allowed 7, one wider than the folk rule). The staggered family is where folklore and arithmetic part ways. The pattern every tutorial repeats — torches every 18 along rows, rows 9 apart, offset 9 — does cover, but it spends one torch per 162 blocks, slightly more than the plain 13 grid's one per 169. Brute-forcing every row-and-offset combination finds the maximum at one torch per 364 blocks, reached by exactly two layouts: 28 wide with rows 13 apart (offset 14) and 26 wide with rows 14 apart (offset 13). Neither can be stretched — from 28×13, both 29×13 and 28×14 open a dark cell — and no other combination beats 364, so there is a best density but not a single best pattern. That 364 sits one block shy of the theoretical ceiling — the perfect diamond tiling covers exactly 365 per torch (2R² + 2R + 1 at R = 13), which our suite also verifies by simulation — so the brick pattern is, for practical purposes, as good as spawn-proofing gets. These parity claims resist one-line proofs, so we do not offer any; the test suite brute-forces every cell of each repeating tile, confirms zero dark spots at the stated maxima, and confirms that one more block breaks each of them.

A worked example

Suppose you are lighting a 100×100 platform. On the legacy rule, a 7-block grid needed 15 torches per row, 225 in total. On the current rule, a 13-block grid needs 8 per row, 64 in all — 161 torches saved by the rule change alone, roughly a third of the old bill. The folk staggered pattern, for all its reputation, lays 6 columns in 12 rows here — 72 torches, MORE than the plain grid, because one torch per 162 blocks (18×9) is slightly denser than the grid's one per 169. The optimal staggered pattern is another story entirely: at 28 wide with rows 13 apart it needs 4 columns in 8 rows — 32 torches, half the grid's bill. The honest conclusion runs in two parts: the rule change did most of the work (225 down to 64), and re-deriving the stagger instead of copying it does the rest (64 down to 32). The 18-by-9 habit is a fossil — it is roughly the legacy-era shape carried forward without re-derivation, from the days when staggering genuinely beat the grid (one per 84 blocks against one per 49 under the old rule, which the suite also verifies, one shy of the legacy ceiling of 85). Lanterns at light 15 stretch the corridor to 29 and, thanks to parity, the grid to 15; soul torches at 10 shrink the grid to 9 and read as decor with a caveat.

What this page deliberately leaves out

Cave lighting through walls (light does not bend around corners — it floods, and a wall changes the taxicab path), slab and carpet spawn-proofing, mob-specific exceptions, and the handful of hostiles with their own light rules. The flat-ground model here is exact for open floors, platforms, and perimeters, which is where torch-spacing questions actually come from; interiors with obstructions deserve the in-game debug screen rather than a formula.

Sources

The one-per-block taxicab falloff and the source levels (torch 14, soul torch 10, lantern, glowstone, sea lantern, and lit campfire 15, single candle 3) are stated on the Minecraft Wiki's light page; the light-zero spawn requirement for Java since 1.18 and Bedrock since 1.18.0 is stated there and on its spawn-proofing tutorial, which also records the 13-block grid; the staggered figures widely repeated elsewhere are the folk 18-by-9 — the 364-per-torch maximum, its two layouts, and the 365 diamond ceiling are not quoted from anywhere — they come from this site's own brute-force simulation, which the test suite re-runs on every build. All re-checked 2026-09-01.