New divers often underestimate the significance of owning a good dive knife: you hardly use it but, when you do, it will be in a life or death situation. No, that doesn’t mean you will use the dive knife to fend off enemy divers. All it will actually do is cut you loose from lines, rope, vegetation, and other stuff that may trap you.
This can be quite scary because, under the water, you can’t call for help and plus nobody will see you if the water is dark. This guide will walk you through the steps needed to find the best dive knife.
Below are the best dive knife options we have chosen for 2019, each one has different functions and price range. Our personal recommendation would be to get a high-quality titanium dive knife to prevent rust problems as if you go diving in saltwater quite frequently if you don’t have an anti-rust blade your blade will end up being useless and you will waste money having to buy a new one.
However, a stainless steel divers knife is easier to sharpen and will still resist rust/ corrosion that’s only if you remember to rinse it after every dive.
The fact they are lightweight and can simply be strapped to your thigh, or placed into your BCD, there is no real excuse not to bring one with you on your next scuba diving adventure.
We have listed next to the name of the knife the best use for it i.e “best dive knife under 50$” or “best dive knife for beginners” this is to help you see quickly which would be the best one for you.
Table of Contents
1. Aqua Lung Argonaut Titanium – Best dive knife
The Aqua Lung Argonaut Titanium dive knife is designed to be the toughest and the absolute best of the Agua Lung knives. This blade has its classic two distinct styles, the Spartan and the Blunt. The handles are wrapped in such a way that it provides a spot for the forefinger extra grip for the sheath.
The reviews for this knife speak for themselves as “the only dive knife you will ever need” it is a little expensive but in the long run you will save money as this will last you a very long time.
2. Tusa X-Pert II Titanium Divers Knife – Best lightweight dive knife 
The Tusa X-Per II diving knife has a distinctively sharp front and a serrated back edge. The line cutter that is included can slice through the line quickly and easily, and the rubber ergonomic grip has to be one of the most comfortable we have gotten tried out.
The sheath is made of a high-quality plastic shell with a handy push-button release that keeps the knife firm and in place until it is needed.
This is a titanium dive knife, so while it takes a bit more effort to sharpen, however, it will stay sharp longer and resist rust from sea salt water far better than other cheaper dive knives. It is also made to be extremely lightweight so if you are looking for a good quality lightweight dive knife this is the one for you.
3. Cressi Alligator – Best Multi-purpose dive knife
The Cressi Alligator is a compact and clever diving knife that can be used as a knife, as well as scissors it is multi-functionality, which makes it useful, and well worth the investment. Its size is small enough to fit in your BCD (mounts are included). The handle is only just 3 inches long however the rubber insets and the wide guards provide a stern grip. This knife is ideal if you want a compact, multi-purpose, top-quality knife.
4. Mares Force Bat Titanium – Best dive knife for beginners 
The Mares Force Bat Titanium offers greater cutting sharpness with its custom-ground blade with unique serrations, allowing you to cut through a variety of materials effortlessly.
The Force Bat can also be easily opened with one hand making it easily accessible in a dire situation. This is our opinion makes it the best dive knife for beginners because it can be opened with one hand making it easy to do so for a novice. Plus it is extremely sharp so it will cut through rope much easier than other dive knives. Plus this is affordable at under $100.
5. Promate Stainless Steel Knife – Best Dive Knife on a Budget
This dive knife by promoting is a great knife and will do the job if you just need a knife with you in case of the worst. It’s stainless steel so you will need to rinse and lubricate it after every use. But ideal if you are on a budget and need to have a knife with you. The blade is sharp and has a quick release function and adjustable straps and sheaths. plus you can disassemble this very easily for maintenance
6. Cressi Skorpion Dive Knife – Dive Knife Under $50
The Cressi Skorpion is the absolute ideal dive knife under $50 and our top pick in case of quality/price. It is a surprisingly versatile scuba diving knife that has the top 3 primary functions most divers look for. There is a serrated back edge that is ideal for cutting and sawing harder materials, a line cutter to safely and quickly cut through even the toughest line, and a sharp front edge to the blade. This diverse knife can be used for spearfishermen as well
The blade is made from anti-rust-resistant stainless steel material which makes it easy to sharpen, just remember to rinse it along with all your other scuba gear after a saltwater dive. This is an extremely affordable dive knife which makes it attractive to a wide range of divers.
7. US Diver’s Titanium knife – Best knife for disablement 
When you see the US Diver’s Titanium knife, This is a very sharp full-size blade (5 inches to be exact) the line cutter is just below the sharp blade, unlike typical dive knives where it is normally found on the back. This blade is full tang, and the entire knife can be disassembled which makes it the best for quick cleaning It is a little more on the expensive side but has great user reviews.
8. Atomic Aquatics Titanium Ti6 – Best All Round Dive Knife
The Atomic Aquatics Titanium Ti6 is a lightweight, sturdy full-size dive knife that works perfectly in most situations, with the exception of heavy prying. It comes with both a serrated and smooth blade for those different types of uses and has a quality-designed sheath. Making this is an excellent choice if you are looking for a versatile knife that will not corrode.
9. Cressi Orca – Best knife for a work tool
The Cressi Orca dive knife has been specially designed to be used as a work tool. It comes up quite bigger and heavier than most other dive knives, making the bigger jobs a lot easier.
Another useful feature this knife has is it has loops to attach the knife to either your leg or onto a belt. It comes with two leg straps. It’s the best option if you are looking for a knife to complete some work underwater.