If you have calipers and a pile of rings (of the same size), this tool will guide you through the process of determining the Actual Aspect Ratio (AR) of those rings.
Close a jump ring and measure its outer diameter.
We recommend measuring the OD at the cut line (kerf) and then rotating the ring 90 degrees and measuring the OD perpendicular to the cut line. We also recommend measuring multiple rings instead of just one.
Click Next when you've entered as many measurements as you'd like.
When measuring, don't squeeze too hard, just apply enough pressure until the ring won't fall out of the caliper jaws.
Use calipers to measure your wire diameter in inch then hit Next below.
As before, when measuring, don't squeeze too hard, just squeeze until you have enough of a grip on the ring that it won't slip out of the caliper jaws.
Here is the actual Aspect Ratio (AR) of the ring size you chose.
To tweak your WD or OD, or to repeat the process with a new size, click the back button to return to either of the two entry fields.