Hook sizing is one of the most confusing topics in fishing for beginners — and the confusion is understandable, because the numbering system runs in two directions that meet in the middle. This guide covers everything needed to select the right hook size for any species, bait, or technique.
How Hook Sizes Work
Fishing hooks are measured by the gap (the distance between the hook point and the shank) and by a numerical scale. The scale runs in two directions from a central point at size 1:
Below size 1 — standard sizes (smaller as the number increases): Size 32 → 22 → 16 → 12 → 10 → 8 → 6 → 4 → 2 → 1 (largest in this range)
Above size 1 — aught sizes (larger as the number increases): 1/0 → 2/0 → 3/0 → 4/0 → 5/0 → 6/0 → 7/0 → 8/0 → 9/0 → 10/0 → …
A size 6 hook is smaller than a size 2. A 2/0 is larger than a size 1. A 10/0 is very large.
Important: Hook sizing is not standardized across manufacturers. A Gamakatsu 3/0 wide-gap may be physically different in size from an Owner 3/0 wide-gap. Always compare the actual hook physical size when switching brands, not just the size number.
Hook Style Affects Effective Size
Beyond the size number, hook style affects how large a hook appears to the fish and how it performs:
| Hook Style | Description | Best Application |
|---|---|---|
| Wide-gap / EWG | Extra-wide gap between point and shank | Soft plastic Texas rigs, creature baits |
| Standard / Aberdeen | Standard gap; lighter wire | Live bait, worms, panfish |
| Circle hook | Inward-turned point | Natural bait, catch-and-release |
| Kahle / Wide-bend | Wide gap, J-hook hybrid | Live and cut bait, catfish |
| Treble hook | Three-point hook | Hard lures (crankbaits, topwater) |
| Octopus | Short shank, wide gap | Snelling, salmon, bait fishing |
| Jig hook | Built into jig head | Jigs, shaky heads, Ned rigs |
Hook Size by Species
Freshwater Species
| Species | Technique | Hook Size | Hook Style |
|---|---|---|---|
| Bluegill / Panfish | Worm, cricket, small jig | 6-10 | Aberdeen, small bait hook |
| Crappie | Minnow, small jig | 2-6 | Aberdeen, light wire |
| Trout (stream) | Worm, salmon egg, Power Bait | 8-14 | Treble (eggs), Aberdeen (worm) |
| Trout (large lake/river) | Live minnow, worm | 6-10 | Aberdeen, circle |
| Largemouth bass — Texas rig | 4-6 inch worm | 3/0-5/0 | Wide-gap EWG |
| Largemouth bass — flipping | Creature bait, 7-10 inch worm | 4/0-6/0 | Heavy-duty wide-gap |
| Largemouth bass — wacky rig | 4-5 inch Senko | 1/0-3/0 | Straight-shank, finesse |
| Largemouth bass — ned rig | 2.75-4 inch plastic | 1-2/0 | Round-bend mushroom head |
| Smallmouth bass | Tube bait, worm | 2/0-4/0 | Wide-gap, tube hook |
| Walleye | Live minnow, nightcrawler | 2-2/0 | Octopus, Aberdeen |
| Walleye — spinner rig | Crawler | 4-8 | Treble or octopus |
| Channel catfish | Cut bait, liver | 2/0-4/0 | Circle, Kahle |
| Blue/flathead catfish | Cut shad, large live bait | 6/0-10/0 | Circle hook |
| Carp | Boilies, corn, bread | 4-10 | Knotless knot hook (size 6-10) |
| Northern pike | Large live bait, lures | 3/0-8/0 | Heavy treble (lures), circle (bait) |
| Musky | Large lures | 5/0-10/0 | Large treble (lures) |
Saltwater — Inshore
| Species | Technique | Hook Size | Hook Style |
|---|---|---|---|
| Speckled trout | Live shrimp, soft plastic | 1/0-3/0 | Circle, wide-gap |
| Red drum / Redfish | Blue crab, shrimp, cut mullet | 3/0-5/0 | Circle hook (inline) |
| Flounder | Bucktail, minnow | 2/0-3/0 | Wide-gap, inline |
| Snook | Live baitfish, shrimp | 3/0-5/0 | Circle, live bait |
| Sheepshead | Fiddler crab, barnacle | 1/0-3/0 | Circle, long-shank |
| Cobia | Live blue crab, eel | 5/0-6/0 | Circle hook |
| Tarpon | Live mullet, crab | 4/0-6/0 | Circle (offshore-style) |
| Bonefish | Small crab, shrimp fly | 2-6 | Bonefish fly hook |
| Permit | Live crab | 2/0-4/0 | Circle hook |
Saltwater — Nearshore and Offshore
| Species | Technique | Hook Size | Hook Style |
|---|---|---|---|
| King mackerel | Live baitfish (stinger rig) | 3/0-5/0 (front) + 2/0-4/0 (treble) | Single + treble stinger |
| Spanish mackerel | Live shrimp, small spoons | 1/0-3/0 | Single live bait |
| Grouper (red, gag) | Cut bait, live bait (bottom) | 7/0-9/0 | Circle hook |
| Snapper (red, mangrove) | Cut bait, live bait | 3/0-7/0 | Circle hook |
| Amberjack | Live bait, jigging | 5/0-8/0 | Heavy-duty circle or J hook |
| Mahi-mahi | Live bait, pitch bait | 5/0-8/0 | Circle or J hook |
| Wahoo | High-speed trolling | 7/0-10/0 | Heavy treble or inline single |
| Tuna (yellowfin) | Chunking, live bait | 7/0-10/0 | Circle hook (inline required federally) |
| Striped bass | Live bunker, chunk | 7/0-9/0 | Circle hook (inline) |
| Striped bass — soft plastic | 5-7 inch paddle tail | 5/0-7/0 | Wide-gap |
| Shark | Cut bait, whole fish | 10/0-16/0 | Circle hook (required in many fisheries) |
| Halibut (Pacific) | Circle hook on bait | 7/0-10/0 | Inline circle |
Matching Hook Size to Bait
Bait size should be the primary driver of hook size — the hook must be large enough to reach outside the bait, but not so large that it dwarfs the bait and becomes visible.
General rule: The hook gap should be roughly equal to 1/3 to 1/2 the length of the bait.
| Bait Type | Bait Size | Suggested Hook Size |
|---|---|---|
| Nightcrawler (half worm) | 3-4 inches | Size 6-8 |
| Nightcrawler (full) | 6-8 inches | Size 2-4 |
| Small shrimp | 2-3 inches | Size 2-1/0 |
| Medium shrimp | 3-4 inches | Size 1/0-2/0 |
| Large shrimp | 4-6 inches | Size 2/0-3/0 |
| Small minnow (1-2 in) | 1-2 inches | Size 6-8 |
| Medium minnow (3-4 in) | 3-4 inches | Size 2-1/0 |
| Large baitfish (6-10 in) | 6-10 inches | Size 3/0-5/0 |
| Fiddler crab | 1-2 inch body | Size 1/0-2/0 |
| Blue crab (half) | 3-4 inch carapace | Size 4/0-5/0 |
| Cut chunk bait | 2-3 oz | Size 4/0-6/0 |
Knots for Hooks
The two best knots for attaching line to a hook:
- Palomar Knot: Works with all hook sizes on mono, fluorocarbon, and braid. Best overall choice (~95% strength).
- Improved Clinch Knot: 6-7 wraps for most hooks; reduces to 4-5 wraps for very large hooks on heavy line where the line fills the wrap space quickly.
- Snell Knot: For circle hooks and octopus hooks where changing the pull direction improves hookup rate.
Related Guides
- J Hook vs Circle Hook — understanding the two main hook designs
- How to Rig a Circle Hook — technique for using circle hooks correctly
- Best Knots for Bass Fishing — hook and knot combinations for all major bass techniques
- Palomar Knot — the most reliable knot for any hook size