Humans are at quite a disadvantage in the water, and it is very easy to be caught in a life or death situation if you’re not properly equipped for it. A dive knife is invaluable if you find yourself snared by a fishing net or rope, or if there are potential predators nearby. Knowing that your trusty knife is within arms reach and ready to be used will give divers of all levels some peace of mind.
With that said, there are many models on the market at various price ranges. For some, money is no object when it comes to buying equipment that can literally save their life. However, not everyone has that luxury, and especially for those starting out there are affordable options that can get the job done as well. In this review, we give our recommendations on the best dive knives under $50, as well as our buying guide, so that even those on a budget can enjoy their hobby knowing that they are prepared for the worst.
Our Top Picks:
Best Dive Knives Under $50 Reviewed
Cressi Skorpion
- Skorpion is a modern knife of the latest generation design and medium dimensions, with a resistant tempered blade of tempered AISI 304 steel, with a...
- The Skorpion is available in two different blades: pointed tip and blunt tip. The blade is long 4 3/8 in (11 cm). The total knife length is 9 1/8 in...
- One side of the stainless steel blade is straight-edged, the other one is serrated right along the blade; they are both very sharp and effective for...
Made of Japanese 420 stainless steel, the Cressi Skorpion is a medium-length knife with a durable blade. The blade measures in at 4 ⅜ in. or 11 cm, with the total length including handle measuring in at 9 ⅛ in. (23.20 cm).
The Skorpion features a stainless steel blade with a straight-edge on one end, with a serrated edge and wire cutter on the other side. You can get it in both pointed and blunt tip, and both are sharp and very effective at line cutting.
The included sheath has a locking mechanism which will keep the sheath safely on the blade, but it can also be released with just one-hand and a push of the polymer thumb tab. Two standard issue straps help connect the sheath to your leg.
Some users have reported that the knife tang (not the blade itself) has a tendency to rust on the surface level only. Make sure to thoroughly rinse with freshwater before storing.
Pros:
- Blunt tip or pointed tip available.
- Has both a straight-edged and serrated edge, with wirecutter included.
- Locking mechanism keeps sheath in place and can be easily released with one hand
Cons:
- Knife tang rusts easily if not properly rinsed.
Aqualung Squeeze Knife
- 304-Series Stainless Steel Blade
- Blunt Tip Design
- Patented Squeeze-Lock Sheath
The Aqualung Squeeze Knife features a 3” (7.6 cm) 304 stainless steel blade with line cutter. With the handle included, the total length is 6.5” (16.5 cm). A diver never wants to lose their knife, and that is why the locking mechanism for the Aqualung sports their patented “Squeeze lock” technology to ensure the knife stays secure in the sheath.
Accessing it with one hand is easy because with just a squeeze of the handle, the locking mechanism releases the knife from the sheath. The blunt tip of the Squeeze knife will prevent any self-injury or gear from being damaged.
The Aqualung provides numerous mounting options through the belt clip on the sheath, with included hose mounting straps and knife grommets for mounting on the BC inflator hose. You can also purchase optional rubber leg straps, as these are not included.
Pros:
- Squeeze lock technology secures and releases knife easily
- Can be mounted on BC for easy access
- 304 stainless steel blade
- Blunt tip
Cons:
- One user felt that the knife was not very sharp, even fresh out of the package.
Cressi Borg
- The Borg is a modern, large knife with a futuristic design and a strong, tempered blade made of 304 Japanese stainless steel
- One side of the stainless steel blade is straight-edged, the other one is serrated right along the blade; they are both very sharp and effective for...
- The handle has an ergonomic design to ensure a secure grip even wearing gloves. It is separated from the blade by a small technopolymer thumb tab
The Cressi Borg is one of the best dive knives with a long blade that can also be used for other water activities like snorkeling, swimming or spear fishing. With an overall length of 10.43 inches and a 5.51” inch blade, it is one of the larger knives on the market. Furthermore, the blade is constructed from 420 stainless steel, which is highly resistant to rust.
With that said, you should still make sure to rinse the knife with fresh water and dry it after each use. If done properly, then the Cressi Borg should last you for years. The blade of the Cressi Borg features a drop point tip, and it features both a serrated edge and a straight edge.
Furthermore, the Cressi Borg comes with a line cutter, which is atypical of a dive knife. Next, the handle has an ergonomic design with finger grips, thumb tab, and excellent grip. The metal butt below the handle can be used as a tap hammer to communicate underwater with a dive partner.
The included sheath is impact resistant, features a quick-release button, and can easily sheathe or release the knife with just one hand. Lastly, the dual leg straps of the sheath can attach to your arm or leg for easy access.
Pros:
- Great for diving, snorkeling, swimming and spearfishing.
- Has both a straight and serrated edge.
- Includes a line cutter and a metal bottom.
- Included sheath has a quick release button and can be used with just one hand.
Cons:
- Some customers complained that the knife guard is made from lower quality materials and will rust if one does not rinse and dry it thoroughly.
Cressi Lima
- The Lima is a great emergency knife for scuba diving and a very desirable knife for the spear fisherman. It is very small and compact. This allows it...
- The blade is made of Japanese stainless steel 304, very resistant to the salt Sea water. The knife is long 6. 3 in (160 mm) and the blade 2. 44 in (62...
- One-hand release sheath mechanism. Back clip for attaching it to the BCD strap or to the weight belt. Hose holder available allowing to attach the...
The Cressi Lima is a lightweight knife that is a bit on the small side. It comes with a durable sheath with a quick-release function that can be operated with just one hand. The blade is doubled-edged, with a straight edge on one side, and a serrated edge on the other that will cut through the thickest and robust ropes.
The blade itself is also highly resistant to corrosion and rusting, and comes pre-sharpened. The blade also has a notch which can be used as a line cutter. Furthermore, the sheath can be attached to numerous parts of your diving kit including your regulator. With how small this blade is, with only a 2.95” blade and weighing only 3.2 ounces, the Cressi Lima is a compact and portable knife. However, that also makes it harder to grip, especially with gloves on.
Pros:
- Great for divers who want a knife that is easily accessible, with numerous ways it can be attached to your diving kit.
- Lightweight and doesn’t take up much space.
- Versatile double-edged blade that also features a line cutter.
Cons:
- Its small size makes it harder to grip, especially with gloves. Consider roughing up the surface of the handle for extra grip.
Promate KF-510 Sharp Tip Stainless Steel Dive Knife
- 304 stainless steel blade
- Stainless steel hammer on handle bottom
- Quick release and adjustable straps and sheaths
The Promate Barracuda KF-510 features a grade 304 stainless steel blade and can be disassembled for easier cleaning and maintenance. The stainless steel butt cap beneath the handle can be used for hammering or getting the attention of other divers.
The lanyard hole located on the handle provides an easy way to carry the knife with you. Adjustable straps provide a tighter fit, and the sheath features a one-hand quick release. Users have found that the KF-510 is very sharp and sturdy.
Pros:
- Sharp 304 stainless steel blade
- Quick release sheath
- Butt cap located beneath handle
- Can be disassembled for easy maintenance
Cons:
- Straps can dig into your legs
- One user reported having issues with comfort when holding the knife
Promate Titanium Blade Dive Knife
- Titanium blade with Easy grip rubber molded handle with sheath and adjustable straps
- Requires little or no maintenance
- Light weight
The titanium blade of the Promate dive knife measures in at 4.45” (11.3 cm) and has a total length of 9.45” (24 cm). It is corrosion and stain resistant, featuring a straight edge full tang blade on one side, and on the other side it has a serrated edge with line cutter.
The knife handle is ergonomic; the durable rubber handle with finger ridges will provide the grip you need no matter the situation. Beneath the handle is a titanium butt which can be used for hammering or as a tank banger to communicate underwater.
You can get the knife blade with a drop point or blunt tip. The blunt tip adds versatility since it can also double as a screwdriver. The sheath is made from a high quality styrene plastic with a double button push release mechanism. This knife comes included with 2 corrosion resistant rubber leg straps to secure your blade on.
Pros:
- Both a straight and serrated edge with line cutter
- Titanium blade is highly durable and sharp
- Blunt or drop point tip
- Titanium butt for hammering or signaling
- Light weight
Cons:
- Some users had issues with the locking mechanism jamming if grains of sand make their way inside, however others disagreed.
What to Look for in a Dive Knife
There are a few major things you should keep in mind when shopping for a dive knife. The material used in the blade and handle are important, as are the knife type and size. Before we get into the reviews, let’s discuss each factor in more detail.
Blade Material
There are two dive knife blade materials to choose from: titanium and stainless steel.
Both have their advantages, however titanium is typically more expensive and stainless steel is the budget option. Whichever material you prefer, you must determine if the blade can hold an edge for a long time, is durable enough to prevent breaking, and resistant enough to avoid corrosion.
Stainless Steel
For economic reasons, most dive knives are made from stainless steel. While it is sturdy and reliable enough, blades made from stainless steel are more susceptible to corrosion. This is important to keep in mind since exposure to salt water will cause it to rust.
If you buy one with a higher carbon count it will resist rust better, but will be tougher to sharpen. Higher grade stainless steel, such as Japanese 420 stainless steel or H1 steel will hold up much better. You must take great care of your blade to keep it from rusting. Rinse both the blade and handle in freshwater, dry it, and coat the blade with oil or grease for extra protection.
Titanium
We believe this is the better of the two materials. Titanium knives are more durable and better at resisting corrosion which is exactly what you need in a blade. One disadvantage is that because they are so strong, sharpening them is more difficult. But, they are lighter than steel and have such good edge retention so this won’t be something you have to worry about for a long time.
Blade Size
How large of a blade size you need depends on what you want to use it for. A blade length of 4-5 inches is a decent middleground best suited for the recreational diver. It will get you out of a pinch if you get tangled up in a fishing line or rope. For a professional such as a spear fisherman, blades larger than 5 inches are recommended. A beginner or casual diver who just needs a small backup knife, then a blade length of 3 inches will suffice.
Edge
There are three types of blade edge to consider: straight, serrated, or partially-serrated. Serrated blades are more effective at cutting tough material like seaweed or rope because their “teeth” can chew through them when used in a sawing motion. Straight blades are better for cutting lines and plastic. Get the best of both worlds with a partially-serrated edge.
Blade Design
Dive knives can have a sharp tip or blunt tip. Blunt tips are recommended for recreational diving because they are so versatile. You can ease them as screwdrivers or for prying things loose and never have to worry about stabbing yourself or poking your gear full of holes.
Sharp tips are the preferred choice for spearfishers and those who actually want to puncture something. Just be wary that you can accidentally injure yourself.
Knife Design
Folding
With a folding knife, the blade can be retracted into a groove in the handle. Folding knives are therefore compact and space efficient. When folded down, it can be easily kept in a BCD pocket, won’t snag on anything, and you don’t have to worry about accidentally cutting yourself when reaching for it. The downside to this type of design is that, in an emergency and especially if a diver is panicking or wearing gloves, they may struggle to open the knife.
Fixed
Fixed blade knives are what most people think of if you ask them to picture a knife in their head. They do not fold and are much more intuitive to use; just take it out of the sheathe and start cutting. They are kept in sheathes, and the sheathes are usually attached to one’s leg, deflator hose, or BCD pocket flap.
With that said, make sure that the knife you have in mind can be mounted the way you’d like because not every sheath provides every option. When diving with a fixed knife, try to find a sheath that has a quick release button so that the knife won’t unexpectedly unsheath, only when you want it to.
Length
The length of diving knife blades typically run between 3 to 6 inches. There are bigger knives but they are more uncomfortable to carry around and might get in the way. The reality is, a smaller dive knife is easier to carry and harness while diving. They can also cut just as well as larger dive knives and are generally more versatile.
With that said, larger knives can afford to have a more comfortable handle. If you are a big guy with large hands or intend on cutting hundreds of feet of line, then you’ll soon realize that a smaller knife with a smaller handle would have been hell to use for that purpose.
Attachments
Folding knives take up less space and can fit in your pocket, generally with a clip so it won’t fall out. Otherwise, blades will come with a sheath that can attach to your leg with straps. Some knives can be carried around your waist, arm, or attached to your BCD. Great care must be taken to avoid snagging it on passing environment, line, or your other equipment. The sheath must have a mechanism to allow the knife to be drawn easily, but firmly held in place when not in use.
Grip
Unless you plan on buying a new dive knife each time, you should consider getting a dive knife that has a good grip. It doesn’t matter what kind of cool features there are or how good the blade is at cutting rope if it ends up at the bottom of the seafloor. With that said, you would be surprised at how often grip design is neglected when shopping for a dive knife. For a knife to have a good grip, consider its shape, texture, and material.
First, consider the ergonomics of the knife. Does it conform to the shape of your hand, or is it awkward to hold and use? Also, will you be wearing gloves when using the knife? If so, consider getting a knife with a larger handle so that it is easier to grab. Grips vary in size, so keep into account your hand size and whether you’ll be wearing gloves.
Generally, dive knives have either pure metal grips, or grips made from rubber or a synthetic material to improve its grip. Some handles are completely smooth, and some have contours to accommodate your fingers. Furthermore, a textured handle increases grip, and a rubber handle helps with this as well.
Visibility
When you’re underwater, visibility can sometimes become an issue. If you have a knife that is a dark color, it will be harder to see it and much easier to lose it. If you lose your grip on your dark knife, it is as good as gone.
A bright colored knife with neon-colored handles might not look the best, but you’ll be able to locate it and reach for it faster. Especially in an emergency, every precious second you spend trying to find your knife could be the difference between life or death. Consider the safety benefits of a highly visible, bright-colored knife.
Sheath
When shopping for a dive knife, don’t neglect looking for a durable sheath because that is the tool that keeps your knife safely on your person instead of sinking into the depths of the ocean. Sheaths also prevent the knife from accidentally stabbing you when you’re not using it, which is most of the time.
When the time arrives, it will be where you will be reaching if you need to grab the knife. A reliable sheath should be securely attached to your body or diving equipment. It should also have a sheath retainer which keeps the knife firmly secured and stops it from unsheathing. If you are using a folded dive knife, many of them come with clips instead.
Metal Butt
When you’re already bringing a lot of equipment with you, you want tools that are versatile and can do multiple jobs so you don’t need to carry as much. Therefore, a dive knife can never have too many features, and a useful feature that only some models have is a metal butt. Essentially, it is just a metal cap beneath the handle. With it, you can use it as a tap hammer which is useful when communicating to your diving partner. Or you can just hit things with it.
Lanyard Hole
This is yet another useful feature that could improve your diving experience. If you have a fear of losing your knife, you’ll find the lanyard hole to be extremely useful because you can keep the lanyard around your hand which can act as a back-up in case you lose your grip. Divers that wear dive gloves and can’t trust their grip should look for a knife with a lanyard hole.
Intended Purpose
If you are in the market for a dive knife for spearfishing, then you want a knife made to dispatch speared fish. To do this, the blade must cut well but the knife must have tools for freeing or repairing spear points.
You may want a knife that can be used for prying, sawing, or heavy pounding. In this case, you need a knife that is durable and strong, with a thick blade, excellent grip, and a hammer on the butt end of the handle.
If all you need is a knife for emergency use, such as to cut entanglements like kelp, fishing lines, and rope, then a compact knife that can be easily accessed will get the job done.
With that said, you may need multiple knives or you may just need a single reliable one; it very much depends on how you want to use your tools.
Conclusion
You don’t want to be caught underwater without a trusty dive knife to get you out of entanglements. The best dive knife should be easily accessible, with a sharp edge to slice through lines, kelp, or other such dangers.
Proper maintenance of your dive knife is crucial in keeping its longevity. After every dive, make sure to rinse both the blade and handle thoroughly with freshwater. Apply some oil or grease for extra protection. If you do this each time, you should not notice any rust or corrosion which would quickly degrade the quality of your knife.
Photo: Eric T Gunther [CC BY-SA]
Last update on 2024-09-17 / Affiliate links / Images from Amazon Product Advertising API