Is there an official standard for sizing tapered cork stoppers?Updated 8 hours ago

No formal sizing standard for tapered or conical corks is currently published by international standards organizations such as ISO, ASTM, or CEN. Instead, cork sizing is based on industry-accepted conventions that have evolved through decades of manufacturing and trade practice.

At Jelinek Cork Group, we follow these conventions and have published our own sizing reference for Regular Length (RL) tapered corks, which you can view here:
 
RL Tapered Corks Sizing Reference Guide

Each RL size corresponds to specific top and bottom diameters and a standard length. In addition to RL corks, other common size designations include Short-Length (SL) and Extra-Long (EL) tapered corks, which follow similar dimensional logic.These sizing systems are widely recognized across the cork industry and help ensure compatibility for a wide range of applications.