Balancer mechanics

Balancers are used to evenly distribute items over multiple belts or multiple belt lanes. Belt balancers are usually used to even out production by placing them in front of large machine arrays with mutiple input belts. Belt balancers are also usually used to balance mutiple belts before or after train stations. Lane balancers are usually placed after production to ensure that a belt is fully compressed or before consumption to ensure that both lanes of the belt are evenly drained.

Lane Balancers

Input Unbalanced, Output Balanced

These balancers evenly distribute the items onto the output lanes but do not "pull" evenly from the input lanes when the output is backed up. They are input unbalanced.
The last balancer is a special case, it only works when there are items on only one side of the input belt.

   File:Corner-lane balancer.png   File:One lane-lane balancer.png

Input and Output Balanced

These balancers evenly distribute the items onto the output lanes and "pull" evenly from the input lanes when the output is backed up. They are input and output balanced.

4 Belts

File:Input balanced-lane balancer-4belt.png   or    File:Input balanced-lane balancer-4belt-smaller.png

Belt Balancers

Theses belt balancers are all tested to be input balanced and output balanced. Throughput under full load and min throughput with all combinations is also tested, it is stated when that is under 100%. Test tests are done using this handy tool by d4rkpl4y3r on the Factorio Forums.

1 belt to x belts

1 to 2

File:1to2 balancer.png

1 to 3

File:1to3 balancer.png

The left output belt is throughput limited.

1 to 4

File:1to4 balancer.png

1 to 5

File:1to5 balancer.png

The left output belt is throughput limited.

1 to 6

File:1to6 balancer.png

The two most left output belts are throughput limited.

1 to 7

File:1to7 balancer.png

The three most right output belts are throughput limited.

1 to 8

File:1to8 balancer.png

1 to 16

File:1to16 balancer.png

2 belts to x belts

2 to 1

File:2to1 balancer.png

2 to 2

File:2to2 balancer.png

2 to 3

• File:2to3 balancer a.png

  Throughput can go down to 75%.
• File:2to3 balancer b.png

  Throughput can go down to 75%. This version has a smaller height but is one tile wider.

2 to 4

File:2to4 balancer.png

Throughput can go down to 50%.

2 to 5

File:2to5 balancer.png

The left output belt is throughput limited. Throughput can go down to 50%.

2 to 6

File:2to6 balancer.png

Throughput can go down to 50%.

2 to 8

File:2to8 balancer.png

Throughput can go down to 50%.

2 to 16

File:2to16 balancer.png

Throughput can go down to 50%.

References

• Command line belt balancer analyzer
• Blueprint String Mod
• Collection of lane balancers
• Collection of belt balancers, most of these contain a lot of unnecessary splitters
• Another collection of belt balancers, some of these are not input balanced
• Another collection of balancers, all of them are input and output balanced. Made by /u/RedditNamesAreShort on reddit