DE to UK clothing size

The short answer

By the formula, DE 40 is UK 14. On brand charts the most common answer is 14 (1 of 2 brands), and 2 different answers are in print.

The formula and the brands' most common answer agree on every size below. Use the brand's own number for the brand you are buying.

DE to UK. The formula column is arithmetic; the brand columns are read from 2 brand charts checked by hand.
DE	UK by formula	Most brands print	Other answers in print
30	4	not published	not published
32	6	not published	not published
34	8	8 (2 of 2)	10: J.Crew
36	10	10 (1 of 2)	12: J.Crew
38	12	12 (1 of 2)	14: J.Crew
40	14	14 (1 of 2)	16: J.Crew
42	16	not published	not published
44	18	not published	not published
46	20	not published	not published
48	22	not published	not published
50	24	not published	not published

Tinted rows: the formula differs from the brands' most common answer. A brand is counted once per answer.

The widest split is at DE 34: brand charts print anything from UK 8 to 10 for the same size.