A list for converting ring sizes between UK , USA, JAPAN.
Many thanks to the NAG (National Association of Goldsmiths for this)
See below the list for some Ring facts.......


UK      US      JAPAN      DIAM      CIRCUMF      EUROPE
            (mm)     (mm)    
H«           4             7             14.8         46.5                 6
I«            41/2         8            15.2          48                    8
J«              5           9              15.6         49                    9
L              5«         10              16           50.5                10
M              6          12           16.4          52                   12
N              6«        13             16.8          53                   13
O               7        14               17.3         54.5                14
P                7«      15               17.7           55.5               15
Q                8       16                18.1            57                 17
Q«              8«      17              18.5            58                  18
R«               9       18             18.9           59.5                 19
S«               9«       20             19.3             61                  21
T«               10      21              19.7            62                   22
U«             10«      22             20.1          63.5                    23
V«             11        24             20.6           64.5                   24
W«             11«      25             21               66                    26
Y                 12      26              21.4          67.5                   27
Z                 12«     27             21.8          68.5                    28
Z+1             13      28              22.2           70                      30
Z+2             13«      29            22.6            71                     31
Z+3             14       31             23              72.5                   32
Z+4             14«      32             23.4           74                      34
Z+5             15        33             23.9          75                        35


Dont forget :-

If your right handed your fingers on the right hand will USUALLY be bigger than the fingers on the left.

The wider the band of a ring the more tightly it tends to fit.
IE if you have a narrow ring as size P that fits you a 10mm band ring as size P will probably NOT.

Just because it goes on doesn't mean its going to come off easily.  What do I mean ??
Many people try on a ring and its a little bit of a squeeze BUT it goes on.  Trying to get it off can be a lot more difficult believe me.
One customer forced a ring on once before I could speak and we had to cut it off of her finger!!!!!

Has a ring been on your finger for a long time and its got to come off but its stuck. Has your finger swollen and a ring has got to come off quick.
DONT PANIC !!!!
The more you wrench at your finger the more puffy and swollen it will get.

Try  some washing up liquid or hand cream.
Try putting the finger under some cold water or in a cup of cold water.
Try some frozen peas on the finger.

If all else fails a ring can be cut off.  I have cut rings off peoples fingers that have been on for a long long time.  Some of the rings have been so tight they have cut into the skin and infections have started. 
Ask your local jeweller if they can perform this service there is a special ring cutting tool.


If all else fails and you need the ring off quick.  Contact your emergency services. 
Yes if your finger is swelling and your ring is stuck things can get bad.......

Hope the above helps some one.  If ever we can help just email or phone or visit us.
Many thanks Simon