UK / AU to EU / ISO ring size

The short answer

By the formula, UK / AU P is EU / ISO 56.

Inner circumference 56.3 mm. Ring sizes are defined by that one measurement, so this conversion is exact up to rounding: US sizes are rounded to the nearest quarter, UK letters to the nearest half.

UK / AU to EU / ISO, by the rule that defines the two systems.
UK / AU	EU / ISO
F	44
G	45
H	46
I	48
J	49
K	50
L	51
M	53
N	54
O	55
P	56
Q	58
R	59
S	60
T	61
U	63
V	64
W	65
X	66
Y	68
Z	69

By rule only: no brand charts are checked for this conversion.

Open the converter EU / ISO to UK / AU

UK / AU	EU / ISO
F	44
G	45
H	46
I	48
J	49
K	50
L	51
M	53
N	54
O	55
P	56
Q	58
R	59
S	60
T	61
U	63
V	64
W	65
X	66
Y	68
Z	69

UK / AU	EU / ISO
F	44
G	45
H	46
I	48
J	49
K	50
L	51
M	53
N	54
O	55
P	56
Q	58
R	59
S	60
T	61
U	63
V	64
W	65
X	66
Y	68
Z	69

UK / AU	EU / ISO
F	44
G	45
H	46
I	48
J	49
K	50
L	51
M	53
N	54
O	55
P	56
Q	58
R	59
S	60
T	61
U	63
V	64
W	65
X	66
Y	68
Z	69