How to Choose the Right Carabiner

Carabiners are essential pieces of climbing gear designed to keep you safe during ascents and descents. However, not all carabiners are the same, and it’s important that you choose the right one to guarantee a safe expedition. In this guide, we’ll break down what a carabiner is and explain the differences between each type to help you pick the best one for your needs.

What Is A Carabiner?

A carabiner is a coupling link with a gate closure that attaches to climbing rope and other climbing equipment. They prevent climbers from falling, help store gear while climbing, assist in belaying and rappelling, and much more. Essentially, carabiners are a do-it-all tool for rock climbers and are an essential piece of safety equipment. 

Choosing the right carabiner comes down to the type of climbing you’ll do, and there are four key areas to focus on during your selection process:

• Shape
• Locking Mechanism
• Gate Type
• Size, Weight & Strength

Carabiner Shapes

D-Shaped Carabiners

D-shaped carabiners are the strongest of the bunch because they shift weight toward the spine, or non-gated, side of the carabiner. They have a smaller gate opening than all of the other shapes except for oval carabiners and are generally more expensive. However, they are incredibly durable and excel in a wide variety of climbing activities.

Asymmetrical D-Shaped Carabiners

Also known as offset D-shaped carabiners, these carabiners function similarly to D-shaped ones but have a wider gate opening and weigh less. The wider gate opening makes it easier to clip them, but these carabiners tend to cost more than standard D-shaped carabiners. Asymmetrical D-shaped carabiners are the most popular type of carabiner among climbers.

Pear Shape Carabiners

Commonly referred to as HMS carabiners, pear-shaped carabiners are most commonly used for belaying and rappelling. These carabiners are usually the largest and heaviest out of all of the shapes, and they have large gate openings for easier clipping. Despite their larger size, HMS carabiners are not as strong as D-shaped or asymmetrical d-shaped carabiners.

Oval Carabiners

Oval carabiners have two identical smoothed and curved ends, which prevents load shifting because the weight is centralized. Oval-shaped carabiners can hold more weight than D-shaped carabiners, but they are not as strong as the other shapes. They also have a smaller gate opening.

Types of Carabiner Gates | Non-Locking

Straight Gate Carabiners

Straight gate carabiners are perhaps the most versatile and widely used type of gate. This is because they are durable and easy to use. They are spring-loaded, so you easily push them in to open and release them to automatically shut. Most quickdraws and cams utilize straight gates. 

Bent Gate Carabiners

Bent gates are durable and slightly curved which makes clipping them easier. Like straight gates, they are spring-loaded and commonly found on quickdraws. 

Wire Gate Carabiners

Wire gates feature a stainless steel wire loop instead of a solid shaft like straight gates or bent gates. This makes wire gate carabiners the lightest option, but they are still very sturdy. The biggest benefit of using wire gate carabiners is that they are less likely to freeze shut in frigid climates, which makes them ideal for alpine adventures.

Locking Gate Carabiners

Locking carabiners function similarly to non-locking carabiners, except for a locking mechanism on the gate that secures it to the nose. These types of carabiners can be non-auto locking or auto-locking. Non-auto locking carabiners, like those with screw-lock gates, require the climber to manually screw the threaded sleeve open or close to release the gate.

Auto-lock carabiners automatically lock shut when the gate is closed, usually using a magnetic or spring-loaded locking mechanism. While locking gate carabiners are heavier and more expensive than non-locking, they provide additional security and extra peace of mind, which is priceless in our opinion. 

Keylock vs. Non-Keylock Carabiners

What has a nose but can’t smell? A carabiner. To all the dads out there, you’re welcome to use that joke to make your kids groan. For everyone else, this is a lesson to learn. Yes, biners have noses, and they are located on the tip of the carabiner that the gate snaps into. The main purpose of the nose is to lock the carabiner with the gate to ensure maximum strength. 

When a carabiner’s nose has a little hook, it is a non-keylock carabiner. On the other hand, a keylock carabiner has no hook and operates more like a jigsaw puzzle piece, locking into place with the carabiner as two perfect puzzle pieces would. 

The hooked nose on non-keylock carabiners can cause snagging and other issues that hinder your ability to properly operate the biner. However, keylock carabiners eliminate that issue, ensuring a smoother clipping experience. Keylock carabiners are far superior to non-keylock for that reason, but the only drawback is that they tend to cost more than non-keylock biners.

Carabiner Weight vs. Strength

The general rule of thumb for climbers is to limit your load as much as possible to stay light. Therefore, you need to make a critical decision when it comes to carabiners, specifically their weight and strength. Larger carabiners are sturdier and can hold more gear, but they will weigh you down more. However, smaller, lighter carabiners have smaller gates, which makes clipping them more difficult. Plus, lightweight carabiners have narrower rod stocks, which means they have a shorter lifespan than heavier models. 

Carabiner kN Strength Ratings Explained

Carabiners rated for climbing activities have minimum strength requirements for each of the three possible orientations. 

• Major Axis: This represents the strength across the length of the carabiner parallel to the spine. This is how carabiners are designed to be loaded.
• Minor Axis: This represents the strength perpendicular to the spine when loaded. Carabiners are not meant to be loaded this way, but they can accidentally rotate while in use. This is referred to as cross-loading.
• Open Gate: This represents the strength of the minor axis but when the gate is open.

Carabiners need to be CE and/or UIAA certified from a trusted manufacturer. These ratings are either laser etched or forged onto the side of the carabiner to designate its strength. The minimum strength ratings for each orientation are as follows:

• Minimum Strength of Major Axis: 20kM
• Minimum Strength of Minor Axis: 7kN
• Minimum Strength of Open Gate: 7kN for D and Asymmetrical D carabiners; 6kN for Pear (HMS) carabiners

How to Choose Carabiners Based on Activity

With the foundation of carabiners in place, you can now pick and choose what features you need to ensure you select the best carabiner for the job. Below is a general guide to help you choose the right carabiner based on the type of climbing you will do.

• Belaying and Rappelling: A Pear-Shaped (HMS) carabiner with a locking mechanism

• Racking Gear: D-Shaped, Asymmetrical D-Shaped, or Oval carabiner

• Sport Climbing Quickdraws: Asymmetrical D-Shaped carabiner with a solid gate or wire gate

• Trad Climbing Quickdraws: Asymmetrical D-Shaped carabiner with a wire gate

Carabiners on a Grand Scale

Hopefully, you now know the fundamentals of carabiners and what to look for when buying them for your next ascent. As always, please put safety first and ensure you are purchasing a carabiner with plenty of strength for the job instead of trying to only use the lightest gear possible. Check out our wide selection of climbing shoes, climbing accessories, and climbing harnesses for more high-quality climbing gear and safety equipment for your journey. For more information on climbing gear, take a look at our other guides on How to Choose Climbing Rope and The Best Bouldering Shoes to learn more about climbing essentials.