SIGNAL STRENGTH

Redstone signal strength ranges from 0 (unpowered) to 15 (full power). Understanding signal decay and analog signals is essential for advanced redstone engineering.

A redstone dust line in Minecraft losing one signal level per block — A signal leaves its source at 15 and loses one level per block of dust, so the fifteenth block is the last one lit.

How Signal Strength Works

Power sources (torches, levers, buttons) emit signal strength 15. As the signal travels through redstone dust, it loses 1 strength per block. After 15 blocks of dust, the signal reaches 0 and stops.

Repeaters refresh the signal back to 15 regardless of input strength. Comparators can read, compare, and subtract signal strengths for analog processing.

Any signal strength of 1 or higher will activate components (pistons, lamps, dispensers). The strength only matters for how far the signal travels through dust, or when using comparators for analog circuits.

Signal Strength Reference Table

Strength	Source Example	Note
15	Redstone Torch, Lever (ON), Button (pressed), Repeater output	Maximum, full power
14	Redstone dust 1 block from source	Loses 1 per block of dust
13	Redstone dust 2 blocks from source
12	Redstone dust 3 blocks from source
11	Redstone dust 4 blocks from source
10	Redstone dust 5 blocks from source
9	Redstone dust 6 blocks from source
8	Redstone dust 7 blocks from source
7	Redstone dust 8 blocks from source	Half power
6	Redstone dust 9 blocks from source
5	Redstone dust 10 blocks from source
4	Redstone dust 11 blocks from source
3	Redstone dust 12 blocks from source
2	Redstone dust 13 blocks from source
1	Redstone dust 14 blocks from source	Minimum power, still activates components
0	No signal / 15+ blocks from source	Unpowered

Comparator Container Readings

Comparators can read the fullness of containers as an analog signal. The output signal strength is proportional to how full the container is:

0, Container is empty

1, Container has at least 1 item (minimum reading)

1-14, Proportional to fullness percentage

15, Container is completely full

Formula: signal = floor(1 + (itemCount / maxItems) * 14)

Practical Applications

Item Sorting

Comparators read hopper contents to determine when to unlock output hoppers, forming the basis of item sorting systems.

Analog Circuits

Signal strength enables analog computing, addition, subtraction, comparison, and threshold detection without binary conversion.

Distance-Based Activation

Place components at specific distances from a power source so only nearby ones activate. Useful for sequential lighting or cascading effects.

Combination Locks

Use comparators in subtract mode to check if multiple inputs match specific values. Only the correct combination produces signal strength 0 (or a target value).

Key Rules to Remember

1. Signal loses 1 strength per block of redstone dust. Maximum travel: 15 blocks.
2. Repeaters always output 15, regardless of input strength.
3. Comparators preserve signal strength. They output exact values in compare and subtract modes.
4. Components activate at any signal strength (1+). Only dust cares about the exact value.
5. Strongly powered blocks power adjacent dust at their signal level. Weakly powered blocks do not power adjacent dust.

Home Next: Quasi-Connectivity

Redstone dust in Minecraft losing one signal level per block — Redstone Signal Strength as it looks in Minecraft: a signal leaves its source at 15 and reaches 0 after fifteen blocks of dust.