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Online ring blank length calculator


I got sick of using my crinkly old ring size chart and having to hand
calculate from it, so I wrote an online ring blank length calculator
(in Javascript so you can see the code if you like). I based the
calculator on the H&S chart I have and what I was taught for wider
bands (e.g. for bands wider than 4mm you take the width subtract 4
and multiply by .5 then add that to the length). The calculator is


The calculator is here: 

Looks cool-- I look forward to trying it out!

For those times when you prefer a printed chart, the best one I’ve
found is a freebie at the Contenti site.

They have other cool downloads, too, but the ring chart is my


Just want to say thanks to Mike for posting this link and being kind
enough to share your very handy calculator! Used it today to make a
ring, just had to convert UK size to US and mm to gauge size
first… : )

Sarah in Wales

Updated free online ring blank length calculator


I’ve recently updated my online ring blank length calculator to
include ring sizes from different countries:

Included are US, UK, EU, Swiss, Japanese, German and Polish ring
sizes, and sheet thickness in either B&S gauge or mm.

I’ve also added an option to download it, so you can run it offline
on your computer or phone (in any browser that supports javascript).

If you have any questions or find any problems with the calculator
please let me know!


For German sizes you better take the diameter than the

e.g. diameter for size 54 = 17.2 mm

17.2 + 2.0 (thickness of material) = 19.2 * 3.1416

Or (less sophisticated): 54 + (2 * 3.1416)

XLS e.g. is quite good at that J