Complete Fishing Hook Guide: With Hook Size Chart

Fishing hooks may seem small compared to other fishing equipment, but their significance in fishing cannot be overstated. In 2005, Forbes magazine listed the fishing hook as one of the top 20 tools in human history!

An increasing number of anglers are using circle hooks across different species, driven by the perceived advantages they offer. These benefits include jaw hooking, which simplifies removal; minimizing gut-hooking, thereby reducing mortality rates; and they are particularly suitable for novice anglers and deep-water scenarios.

We have compiled this guide to circle fishing hooks so that you can be confident that the next time you cast your line, you have the best chance of hooking your target fish!

The Anatomy of a circle hook

Fishing hooks have several key parts that contribute to their effectiveness and versatility. These include the eye, shank, point, and barb, which vary across hook styles.

The eye is the connection point to the fishing line or lure. The point is the sharp end penetrating the fish's mouth, available in various shapes requiring regular sharpening. The shank determines the length from the eye to the bend and influences how the hook is used. Lastly, the barb keeps the hook securely in place, and anglers may adjust its size for easier hook removal during catch and release.

A circle hook is a fish hook with a distinctive curved shape, forming a rough circular pattern.

What Are the Benefits of a Circle Hook?

Circle hooks are specifically designed to hook fish in the corner of the mouth, making it easier to release them. The efficacy of circle hooks in minimizing fish injuries and allowing easier unhooking has been documented in department studies and experiences from many states. Circle hooks have proven successful with dead and live baits across various species. 

When using circle hooks, anglers employ a finesse technique known as a "dead stick" or still rod, avoiding the need for forceful rod pulling to set the hook giving a less strenuous reeling-in process. Compared to J-hooks, circle hooks have demonstrated a lower incidence of deep hooking, which can cause organ damage and mortality in fish. By reducing deep hooking and shortening de-hooking times, circle hooks significantly improve the survivability of many species during catch and release, like striped bass, according to the Maryland Department of Natural Resources. 

What Size Circle Hook Should I Use?

The choice of hook size depends on the size of the fish you're targeting and its mouth size. For example, even if a five-pound carp and a five-pound bass are similar in weight, you'll need a smaller hook to catch the carp due to its smaller mouth.

When using any bait, it is essential to consider the size of the hook concerning the bait. Keeping it alive and allowing it to move naturally are crucial factors when using live bait. Consequently, smaller hooks are recommended in such situations. On the other hand, when using dead or cut bait, the priority is ensuring that the hook can penetrate the meat effectively and achieve a secure hook set. Therefore, larger hooks are typically more suitable for these types of bait.

How Do Hook Sizes Work?

Fishing hooks are commonly measured in millimeters, but the displayed hook size is often indicated using a scale that may be obscure to inexperienced individuals.

Circle hook size operates in the same way as all others. Fishing hooks are typically categorized by numbers that indicate their size, ranging from the smallest (#32) to the largest (size 19/0). The numbering system operates inversely in the range of hook sizes from #32 to #1: a higher number denotes a smaller hook size.

On the other hand, for hook sizes from 1/0 (referred to as "one aught") to 19/0, the numbering system aligns with the hook's size. Consequently, a larger number corresponds to a larger hook size.

Popular manufacturers have different ways of sizing their hooks, so do not take for granted that each will be the same. “Some manufacturers base the size on gap size, while others base it on the overall length of the hook.” Matt Gray, Category manager of Eagle Claw Fishing Tackle.

 

Fishing Hook Size Chart

Here is a clear and defined fishing hook size chart. You can consult the hook size with bait and target fish species

Size	Length (mm)	Gap (mm)	Length (inches)	Gap (inches)
#12	9mm	3mm	0.35″	0.118″
#11	10mm	4mm	0.39″	0.157″
#10	11mm	5mm	0.43″	0.196″
#9	12mm	6mm	0.47″	0.236″
#8	13mm	7mm	0.51″	0.27″
#7	14mm	8mm	0.55″	0.31″
#6	15mm	9mm	0.59″	0.35″
#5	16mm	11mm	0.63″	0.43″
#4	17mm	12mm	0.67″	0.47″
#3	20mm	13mm	0.78″	0.51″
#2	22mm	14mm	0.86″	0.55″
#1	25mm	15mm	0.98″”	0.59″”
1/0	34mm	16mm	1.33″	0.63″
2/0	39mm	17mm	1.53″	0.67″
3/0	42mm	18mm	1.65″	0.70″
4/0	47mm	19mm	1.85″	0.74″
5/0	52mm	21mm	2.04″	0.82″
6/0	59mm	23mm	2.32″	0.90″
7/0	65mm	25mm	2.56″	0.98″
8/0	72mm	28mm	2.83″	1.10″
9/0	78mm	31mm	3.07″	1.22″
10/0	90mm	37mm	3.54″	1.45″

 

Freshwater Fishing Hook Sizes

For freshwater fishing, hook sizes vary widely to match the fish species being targeted:

Small Fish: Sizes 32 to 14 are ideal for tiny fish like small trout and panfish.

Medium Fish: Sizes 12 to 1 are best for medium-sized fish such as larger trout, bass, and walleye.

Large Fish: Aught sizes start from 1/0 and go up to around 6/0 for large fish like pike and catfish.

When selecting a hook, consider the type of bait you'll use and the mouth size of the fish species targeted. A proper match between the hook size and the bait size increases the chance of successful hook-ups and reduces harm to the fish.

 

Which Fish Can I Catch with a Circle Hook?

The type of fish you target will influence the hook you choose. Different fish require specific hook designs and features to maximize effectiveness. Several studies have indicated that circle hooks have a higher incidence of mouth-hooking fish than conventional "J" pattern hooks. Before getting on the water, researching your fishing location, conditions, and inhabitants is valuable for optimizing your experience. Equally, speaking with local anglers is always a good idea if you are looking for tips.

The chart below shows excellent results using circle hooks, according to the New South Wales Department of Primary Industries.

Species studied	Percentage of mouth-hooked fish
Yellowfin Bream	up to 90%
Sand/Dusky Flathead	up to 96%
Silver Perch	up to 79%
Red Drum (similar to Mulloway)	up to 96%
Sailfish	up to 98%
Atlantic Bluefin Tuna	up to 94%
Yellowfin Tuna	up to 95%
White Marlin (similar to Striped Marlin)	up to 100%

 

What is the Most Used Hook Size?

The most used hook size depends on the angler's target fish! The most common hook sizes in freshwater fishing range from #20 for flies to larger 10/0 hooks for catfish. On the other hand, in saltwater and boat fishing, the hook sizes tend to be even larger to handle the bigger catches available.

Bait Type

There are several bait factors to consider when deciding which hook to use for your time on the water. Matching the hook size to the bait size will make your hook more likely to snag the fish when it is lured in. 

When utilizing smaller circle hooks for fishing, it is advisable to match them with smaller bait options. Smaller baits have reduced length and weight, making them easier to cast from shore and boat and easier to reel in. Many circle hooks are designed with a short shank, which is particularly suitable for live and cut bait that rests in the bend of the hook. On the other hand, soft baits such as clams and worms are threaded onto the shank, making a longer shank more advantageous for these types of baits.

Some baits mimic natural prey movement; thus, the hooks allowing free bait movement will likely garner more attraction.

Hooking and Safe Release

When fishing, it is important to follow certain practices to ensure successful hooking and safe release. Instead of burying the hook, especially with tougher baits, it is recommended to lightly hook the bait so that the point and barb remain exposed or bridle the bait (a piece of rigging floss or wire is worked through the bait's eye socket forward of the eye. The hook is then attached to the wire or floss). 

When you feel a bite, it is crucial not to strike at the fish immediately; rather, allow the fish sufficient time to take the bait into its mouth. For best mouth-hooking results, non-offset circle hooks are highly recommended. Then, apply slow and steady pressure to set the hook in the mouth area, as the fish often hook themselves.

To better understand how to set the hook, watch for typical indications of a fish biting, such as your bobber being fully submerged, feeling a distinct tug on your fishing line, or observing your fishing line in motion. Although setting the hook is straightforward, distinguishing between an actual bite and other factors like the current or a fish bumping into the bait can sometimes be challenging. Reel in any slack and maintain tension on the line with your bait or lure, as this enhances sensitivity and enables you to detect fish bites more effectively, putting you in a favorable position to set the hook.

Lastly, using a de-hooker or needle-nosed pliers can assist in safe and efficient unhooking. These practices contribute to responsible fishing and the well-being of the fish.

Regulations and Ethical Considerations

Catch-and-release fishing can be an ethical choice or government-regulated activity that looks to respect the immediate environmental conditions and its inhabitants. Choosing the right hook type is vital for the success of catch and release strategies. Options like barbless or circle hooks are safer for fish and help reduce the risk of post-release mortality, according to Czarkowski, T. K., Kupren, K., & Kapusta, A. (2023). Fish Hooks and the Protection of Living Aquatic Resources in the Context of Recreational Catch-and-Release Fishing Practice and Fishing Tourism. Fortunately, using alternative hook types does not necessarily mean sacrificing fishing efficiency significantly, as it was also noted that these hooks do not significantly affect catching rates.

How to Maintain Hooks

Use safety pins of different sizes to maintain your fishing hooks organized and prevent tangling. Larger safety pins are suitable for bigger hooks, while smaller ones work well for smaller hooks. Arrange the safety pins in your tackle trays' compartments according to hook size and type for easy organization. After using your fishing tackle, especially during saltwater fishing, having a small jug or bucket of fresh water on hand is beneficial. Give your fishing tackle a thorough rinse with fresh water before returning it to your tackle box. This simple step helps protect your hooks from rusting or corroding, ensuring their longevity and effectiveness.

Sharpening Techniques for Optimal Hook Performance

For anglers concerned about optimizing hook performance,  sharpening your hooks using a mill file (bastard cut) with fine teeth is more practical than a whetstone. These files can be found at most hardware stores and are quite affordable. Opt for a file that is around 5 to 8 inches long, as it is ideal for sharpening most hooks. The longer length gives a better grip, enabling anglers to cut full and deep strokes into the hook wire or steel. It's important to note that all strokes with the file, or any sharpening device, should be directed toward the hook point and never against it or to its sides. Sharpening from different directions can dull the hook instead of enhancing its sharpness.

Signs of Hook Replacement

To determine when it's necessary to replace a hook, the key factor is the sharpness of the point. Inspecting the hooks before using them is sensible, and after reeling in the rig. If there is no obvious damage to the hook, you can use the thumbnail test by gently running the hook along the nail's surface and towards the edge. If it tends to glide over without gripping the surface, it is not sharp and may need to be discarded.

Proper Disposal of Damaged Hooks

When it comes to disposing of damaged hooks, there are several ways in which you can safely and ethically do this. Some anglers like to cut the dulled ends to ensure they do not injure someone who may handle them later. Other ideas are to stick the hooks into cardboard and later recycle that or to collect them in a bottle and fill that up before responsibly disposing of the bottle. In the city of Loveland, Colorado, the local government encourage individuals to dispose of hooks and other fishing gear in the recycling tubes and bins that are provided in natural areas. Different areas have varying degrees of inter-recycling, so it could be a good idea to check with your local council the regulations regarding the ethical and responsible disposal of your fishing gear.

In Conclusion

Fishing is more than just casting a line and waiting for a fish to take the bait. There is a subtle science to understanding how to set up equipment and maximize your situation. With a diligent attitude to learning the basics, a disciplined routine, and a passion for improving, there is no reason why you cannot become a proficient angler and be reeling in the big ones in no time!

We hope you have enjoyed our guide to circle fishing hooks and that it will be useful for your future angling trips.