Sources & references
The ISO catalogue describes ISO 8653:2016 and its measurement/designation scope. The JSA catalogue identifies JIS S 4700:2022. Catalogue pages do not expose the full standards tables. We do not claim a licensed, row-by-row standards certification.
Standards and evidence limits
The ISO catalogue describes ISO 8653:2016 and its measurement/designation scope. The JSA catalogue identifies JIS S 4700:2022. Catalogue pages do not expose the full standards tables. We do not claim a licensed, row-by-row standards certification.
Why two charts can differ
Our US 7 row uses UK N½ and JP 14; Blue Nile’s international chart, page 2, gives the same labels and rounds diameter to 17.3 mm. This checks that row against one retailer, not every manufacturer or a licensed standards table.
Calculation and rounding
The stored chart has US 3–13 in half-size steps. Diameter is displayed to two decimals and circumference to one. EU is a rounded circumference label; CH, IT and ES use that label minus 40. UK and JP are chart lookups. India and China are not supported systems.
From chart size to fit
Use the intended finger, hand, band width and inner profile. Wider bands may feel tighter; comfort-fit is a different inner profile and does not imply a universal size increase. Follow the exact manufacturer guide and try a matching physical sizer.