Table_title: Master Hook Size Chart Table_content: header: | Hook Size | Gap Width | Typical Application | row: | Hook Size: 9/0 | Tackle Room
Note: Measurements can vary slightly by brand (Mustad vs. Owner vs. Gamakatsu), but these are the industry standard approximations for the width. Gap Width (Approx. mm)
| If you are... | Use a mm chart? | |---------------|----------------| | Casual weekend angler | Helpful but not necessary – stick to brand-specific sizing | | Fly tier or match-the-hatch fisherman | | | Saltwater or big game angler | Yes – for comparing heavy-gauge hooks | | Buying from multiple brands | Yes – prevents mismatched sizes | | Beginner | Learn traditional sizes first, then mm chart for fine-tuning |
– Excellent for technical anglers, slightly confusing for beginners.
These are "aught" sizes. As the number before the slash gets larger, the hook gets larger. A 10/0 is a massive hook for ocean predators. Fishing Hook Size Chart (Approximate MM)
If you use a 5/0 hook with a 2-inch minnow, the bait will not swim naturally, and the fish will feel metal before tasting food. The hook gap should never exceed the width of the baitfish’s body.