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Climbing Gear Strength Ratings

Ever wonder how strong that pro or gear really is?  Here’s a list to get you started, and maybe help you win an argument or two.  I wanted to see a list like this for a long time, and after scouring the web and not finding any, decided to make my own. 

Metric notes:  A kilonewton (kN) is a metric unit of force. 1 kN is equal to about 100 kg / 225 lbs.  Ratings are rounded to the nearest kN.

Sources:  http://www.fishproducts.com, tech pages, “The Mountaineering Handbook”, by Craig Connally, the always awesome Petzl website, various web retailers, checking the gear ratings on some of my own stuff and in the local gear shop.

I made two lists. One is gear ranked in descending order, and the other is gear ranked by category (like seeing small, medium and large stoppers all ranked side by side.)



Takeaways (for me)

  • Even with a severe factor 1 fall, the force on the belayer is only a tiny 2 kN.

  • There's a BIG increase in strength from 6mm cord to 7 mm cord. Use 7 mm for cordelettes.

  • A tiny wiregate carabiner may be stronger than a honker "belay" style carabiner.

  • A well placed bolt is never going to fail you.

  • You can almost rappel on your shoelaces; 2 kN is about the most force you can apply to the anchor.

  • Climbing ropes are not tested for tensile breaking strength like most other gear. Because they are so stretchy, they absorb a huge amount of force before they have a break. But, if you stretch a rope until it breaks, that will probably happen between 14 and 18 kN. Click each link to see the relevant test results. 14 kN was for an old crusty rope, 18 kN was for a new one. Either one is super good enough.


Here's a video for our friends at Hownot2.com, breaking an older rope. Start at 9:45.