Brooks to Allbirds shoe size

The short answer

Brooks 8 is Allbirds 8 by the two brands' own charts. 0 of 13 Brooks sizes land on a different label at Allbirds.

At least one of the two brands publishes no foot length, so the rows line up the US size both charts print. Treat it as the label conversion, not a fit.

Every Brooks size read across to Allbirds. US women's sizes on the left, US women's on the right.
Brooks	Brooks builds it for	Allbirds, by chart	Same label	Allbirds builds it for	Allbirds also prints
5	not published	5	not published	not published	UK 2 to 2.5 · CM / JP 22
5.5	not published	5.5	not published	not published	UK 2.5 · CM / JP 22.5
6	not published	6	not published	not published	UK 3 to 3.5 · CM / JP 23
6.5	not published	6.5	not published	not published	UK 3.5 · CM / JP 23.5
7	not published	7	not published	not published	UK 4 to 4.5 · CM / JP 24
7.5	not published	7.5	not published	not published	UK 4.5 · CM / JP 24.5
8	not published	8	not published	not published	UK 5 to 5.5 · CM / JP 25
8.5	not published	8.5	not published	not published	UK 5.5 · CM / JP 25.5
9	not published	9	not published	not published	UK 6 to 6.5 · CM / JP 26
9.5	not published	9.5	not published	not published	UK 6.5 · CM / JP 26.5
10	not published	10	not published	not published	UK 7 to 7.5 · CM / JP 27
10.5	not published	10.5	not published	not published	UK 7.5 · CM / JP 27.5
11	not published	11	not published	not published	UK 8 to 8.5 · CM / JP 28
11.5	not published	not made	not published	not published	not published
12	not published	not made	not published	not published	not published
12.5	not published	not made	not published	not published	not published
13	not published	not made	not published	not published	not published

Tinted rows change label or sit between two sizes. 4 sizes have no counterpart on the Allbirds chart. Read from the two charts only; no formula and no averaging.

What wearers say

Charts describe a garment. People who own both brands describe a fit, and their answer ranks above this table once five of them stand behind it. Pick your size in the converter to see whether there are enough yet.

Open in the converter Add an item you own

Sources

Brooks size guide, read on 2026-09-17. Brooks on TrueToSize
Allbirds size guide, read on 2026-09-18. Allbirds on TrueToSize

Allbirds to Brooks