Video: O-Ring Sizing Tools

For accurate o-ring sizing, use these tools which can all be purchased on the Global O-Ring and Seal website.

  • Laminated O-Ring Size Chart – An easy to use flip chart showing silhouettes of 239 different sizes of O-Rings. Simply place the o-ring on the chart to match the correct size.
  • O-Ring Sizing Cone – This O-Ring Cone measures 184 of the most popular size O-Rings from ¼” ID to 5-5/8″ ID in five standard cross sections (.070″, .103″, .139″, .210″, and .275″). This cone will provide the user with O-Ring dash numbers instantly. Just slip the O-Ring into the proper slot to determine the cross section. Then place the O-Ring onto the cone and adjust to the proper step to determine the AS568 size dash number above the slot.
  • Gauge – Slide gauge for measuring standard cross section o-rings with an inside diameter up to 13″.
  • Digital Caliper – A preferred tool for precise measurement, our sliding caliper can measure the diameter and length of many components – not just o-rings.
  • O-Sizer Tape – This specially designed o-ring measuring tape comes in three different sizes and is used to measure the ID of metric and AS568 o-rings up to 26 inches.
  • Pi-Tape – Our precision engineered pi-tapes are the most precise tool for measuring the inside diameter of an o-ring to the thousandths of an inch. We offer several different sizes of pi-tapes, depending on the ID size needing to be measured.


Global O-Ring carries a full line of o-rings in all standard AS568 and metric sizes. We’re also here to guide you through the sizing process. Call or come visit our Houston warehouse for more help on sizing o-rings.

Related Posts