For climbers, a locking carabiner is not just a piece of gear; it’s a fundamental safety component. The right locking biner provides a secure, reliable connection for belaying, rappelling, and building anchors, giving you the confidence to focus on the climb. With various locking mechanisms, shapes, and materials available, choosing the best one for your needs is crucial.
This roundup examines nine locking carabiners, from heavy-duty climbing models to versatile everyday organizers. Whether you’re leading a multi-pitch route or just need a secure way to manage your keys, understanding the features and intended use of each carabiner will help you make an informed decision for your safety and convenience.
Our Top Picks for Locking Carabiners
- Emoly 5 Pack Locking Carabiner Clip D Shape
- Nite Ize S-Biner Slide Lock Carabiner, Black
- Carabiner SlideLock No3 Orange
- BLACK DIAMOND RockLock Screwgate Carabiner
- Petzl William Screw-Lock Carabiner
- Mammut Crag Key Lock Bent Gate Carabiner
- DMM Ceros Screwgate
- Black Diamond GridLock Magnetron Locking Carabiner
- Petzl Am’D Ball-Lock Carabiner
Emoly 5 Pack Locking Carabiner Clip D Shape
This five-pack of D-shaped carabiners offers excellent value for general organization. The spring-loaded gate with a screw-lock collar provides a secure closure for items like keys, water bottles, or gear bags, preventing accidental openings. They are compact and designed for convenient one-handed operation.
Constructed from lightweight aircraft aluminum, these carabiners are durable for everyday use while remaining easy to carry. It is important to note the manufacturer specifies these are not applicable for climbing or hanging hammocks. They are best suited for securing gear during camping, hiking, travel, or as heavy-duty keychains.
Nite Ize S-Biner Slide Lock Carabiner, Black
The Nite Ize S-Biner Slide Lock features a unique dual-gate, “S” shaped design made from solid stainless steel. Each gate has a separate sliding lock mechanism, allowing you to securely attach items like keys to one side while frequently clipping and unclipping the other side to a backpack or belt loop. This design keeps your key ring undisturbed.
Rated for 75 pounds, this carabiner is built for strength in everyday carry situations. The stainless steel construction resists corrosion, and the plastic SlideLocks provide positive, tactile feedback when engaged. It’s a robust upgrade from basic key rings for anyone who needs organized, secure attachment points for daily essentials.
Carabiner SlideLock No3 Orange
This orange SlideLock carabiner from Nite Ize combines high visibility with secure functionality. It features a single stainless steel gate with a plastic SlideLock mechanism that slides over the gate to prevent it from accidentally opening. The lightweight aluminum body makes it easy to carry while maintaining a 25-pound weight rating.
The bright color makes it simple to locate on a gear loop or in a bag. Like its sibling products, this model is engineered for securing keys and small valuables in everyday scenarios. Its straightforward locking design provides a reliable alternative to non-locking carabiners for general use.
BLACK DIAMOND RockLock Screwgate Carabiner
The Black Diamond RockLock is a large, HMS (pear-shaped) locking carabiner built for serious climbing applications. Its spacious design is perfect for belaying, rappelling, and constructing anchor systems, as it easily accommodates knots and belay devices. The hot-forged construction provides a strong and lightweight foundation.
A key feature is the Keylock nose, which eliminates the traditional hook-shaped gate. This prevents snagging on ropes, slings, or other gear, allowing for smooth and fast clipping. As a screwgate carabiner, it offers a familiar, manually secured locking mechanism trusted by climbers for critical safety connections.
Petzl William Screw-Lock Carabiner
The Petzl William is a large, asymmetrical pear-shaped locking carabiner designed for belay stations and use with a Munter hitch. Its optimized shape provides a large basket to hold multiple pieces of equipment and facilitates smooth rope movement. The Keylock system ensures a snag-free nose for reliable operation.
Ergonomics are a highlight, with a shape designed for a better grip, even when wearing gloves. The screw-lock mechanism is simple and reliable, performing well in harsh conditions where dirt or ice might compromise automatic lockers. A red band on the locking sleeve offers a clear visual warning when the gate is not fully closed.
Mammut Crag Key Lock Bent Gate Carabiner
The Mammut Crag is a bent-gate locking carabiner, a design favored by many sport climbers for quick and easy rope clipping. The bent gate helps guide the rope smoothly into the carabiner during lead climbs. It features a Keylock nose to prevent snagging on bolts or other gear.
With a strong vertical breaking load of 24 kN, this carabiner is built to withstand the forces of climbing falls. The bent gate design, combined with a secure locking mechanism, makes it a specialized tool for climbers looking to increase their clipping speed and efficiency on routes.
DMM Ceros Screwgate
The DMM Ceros Screwgate is designed with thoughtful features to aid in safety and usability. Its shape is engineered to be effortless to use and rack on a harness. A significant safety feature is the spine-side spring clip, which helps prevent the carabiner from being cross-loaded on a harness gear loop.
This design means the carabiner defaults to a safe, upright position if not placed correctly, reducing the chance of error when you’re gearing up. The screwgate locking mechanism provides a secure closure, making the Ceros a reliable choice for climbers who value innovative safety-oriented design in their equipment.
Black Diamond GridLock Magnetron Locking Carabiner
The Black Diamond GridLock Magnetron employs a magnetic locking mechanism for one-handed operation. Instead of a traditional screw sleeve, it uses a magnetic ball-lock system that automatically engages when the gate closes. This allows for fast and easy locking, which can be advantageous in situations requiring repeated clipping.
Magnetron technology is designed to be reliable and easy to use with one hand, even while wearing gloves. The GridLock model typically offers a solid, wire-gate construction that is both strong and lightweight. This carabiner is suited for climbers looking for a quick-locking option for belaying or general clipping duties.
Petzl Am’D Ball-Lock Carabiner
The Petzl Am’D Ball-Lock carabiner features an automatic ball-lock mechanism. This system uses a spring-loaded ball bearing that securely locks the gate when it closes. To open, you simply press the colored sleeve to retract the ball and open the gate, allowing for simple one-handed operation.
This type of automatic locker is popular for its speed and convenience in many climbing scenarios. The Am’D is built to be robust and reliable, suitable for belaying, rappelling, and anchoring. Its automatic nature means there’s no screw sleeve to manually tighten, which can save time during complex sequences.
How to Choose the Best Locking Carabiners for Climbing
Picking the right locking carabiner isn’t just about grabbing the shiniest one off the shelf. It’s a critical safety decision. I’ve learned that the best tool for the job depends heavily on what that job actually is. Let’s break down what I always check for when I’m adding to my rack.
First, you need to know the two main types: screwgate and auto-locking. A screwgate is the classic design. You manually screw the sleeve down to lock it. They’re simple, reliable, and easy to operate with one hand, which is why I use them for most of my belaying. Auto-locking carabiners (like twist-lock or magnetic gates) have a mechanism that automatically closes and locks. These are fantastic for situations where you might forget to screw it shut, like when you’re setting up a complex anchor and your mind is elsewhere. They add a layer of safety but can be trickier to manipulate with thick gloves on.
Next, consider the shape and gate type. An oval carabiner is symmetrical and works well for clipping multiple pieces of gear or slings, as it doesn’t twist them. A D-shaped carabiner is stronger for its weight because the load is directed down the spine. For most of my climbing, I go with a D-shape. Then there’s the gate itself. A wire gate is light, fast to clip, and less prone to freezing shut in cold weather. A solid gate is more durable and feels smoother to operate. For my quickdraws, I love wire gates for the weight savings. For my belay device or anchor, I often prefer the solid feel of a solid gate.
Strength ratings are non-negotiable. Every carabiner is stamped with three numbers: major axis strength (along the spine), minor axis strength (across the gate), and open gate strength. For any serious climbing, you want a major axis strength of at least 22 kN (kilonewtons). That’s the standard for climbing-rated locking carabiners. The minor and open gate strengths are much lower, which is exactly why we lock them—to prevent a cross-loaded or open gate failure.
Finally, think about weight and size. If you’re a trad climber racking up 15 of these, every gram counts, and a sleek, light wire-gate screwgate might be your pick. For belaying at the crag or building a bomber anchor, a larger, more ergonomic carabiner with a wide mouth for easy clipping is worth the extra few grams. My advice? Start with a versatile, medium-sized screwgate for your first belay carabiner, and then build your collection based on the specific needs of your climbing style. Getting the right locking carabiners for climbing is a foundational step for safe adventures.
FAQ
How often should I retire my locking carabiners?
There’s no strict timeline, but you need to inspect them before every single use. Look for cracks, deep gouges, sharp burrs (especially around the gate), and any stickiness or grinding in the gate mechanism. If a carabiner has taken a serious fall or been dropped from a significant height onto a hard surface, it’s time to retire it. Microscopic damage isn’t always visible. When in doubt, I replace it. It’s not worth the risk.
Can I use any locking carabiner for belaying?
Technically, if it’s climbing-rated (22+ kN), yes. But not all are ideal. For belaying, I specifically look for an HMS or pear-shaped carabiner. This shape is designed to accommodate a belay device properly, preventing it from getting stuck in awkward positions and allowing it to rotate freely for smooth rope handling. Using a small, oval carabiner can make belaying a frustrating and less safe experience.
What’s the difference between a screwgate and a twist-lock?
Both are locking, but they work differently. A screwgate requires you to manually thread the sleeve down until it stops. A twist-lock (like Petzl’s Ball-Lock or a triple-action auto-locker) requires two or three distinct motions to open—usually pushing and twisting. Twist-locks are auto-locking, meaning they snap shut and lock on their own, which is a great safety feature. Screwgates are simpler and often faster for repeated clipping, like at a busy sport crag.
Is a heavier carabiner always stronger?
Not at all. Modern materials and engineering mean strength is not directly tied to weight. A lightweight aluminum wire-gate carabiner can have the same 22+ kN major axis strength as a much heavier solid-gate model. The weight difference usually comes from the gate design and the amount of material used. I choose based on the intended use—saving weight on my rack or prioritizing durability and feel for my belay biner.
Why are there different strength ratings on one carabiner?
Those three numbers tell you how the carabiner performs under different types of loading. The highest number is for a load pulling straight down the spine (major axis). The lower “cross-load” rating is for force applied across the gate (minor axis). The lowest “open gate” rating is for when the gate is open and load is applied. This shows why proper, locked use is so critical—it ensures the carabiner performs at its strongest possible rating.