For most situations, size 4–8 carp hooks are the sweet spot, with size 6 or 8 being the most commonly recommended for average‑sized carp and typical baits like 10–15 mm boilies.

Quick Scoop: What size hook for carp?

Think of carp hooks in a simple range:

  • General rule of thumb: Use hooks between size 2 and 10 for carp.
  • Everyday carp fishing (10–20 lb fish):
    • Size 8–10 for smaller, wary carp or when using small baits.
* Size **6–8** for typical “runs water” carp on 10–15 mm boilies.
  • Bigger carp (20–30 lb+):
    • Size 6–4 , sometimes up to size 2 with larger baits like 20 mm+ boilies.

A simple way to picture it: the bigger the bait and fish, the smaller the hook number (so a size 4 is physically bigger than a size 8).

Mini guide by bait type

  • 10–12 mm boilies: Size 8 (or 10) keeps the rig neat but still strong.
  • 15–18 mm boilies: Size 6 is widely recommended.
  • 20 mm+ boilies: Size 4–2 so the hook can properly grab and hold.
  • Worms / natural baits: Size 8 for smaller pieces; size 6–4 for whole or large worms.

What about hook size vs carp size?

Here’s a simple story‑style example. Imagine:

You’re on a small UK lake, most carp are around 10–15 lb, and you’re fishing 15 mm boilies over a light spread. You’d clip on a size 6 or 8 wide‑gape pattern and be “in the zone” 90% of the time.

In rough terms:

  • Around 10 lb carp: Size 10–8 works best because of their smaller mouths.
  • Up to ~20 lb carp: Size 6–10 , chosen mainly by bait size and how wary the fish are.
  • Around 30 lb carp and up: Size 6–2 , especially with big boilies and strong tackle.

Forum‑style perspective

On forums, anglers often say they:

“Use 10 mm baits on size 6–8 hooks and rarely need to go bigger unless they’re specifically targeting real lumps.”

Others point out that UK anglers tend to favor smaller, sharper hooks with hair rigs , while some US anglers use much larger hooks because the bait goes directly on the hook rather than on a hair.

So the “best” size isn’t one magic number; it’s matching:

  • Hook size
  • Bait size
  • Average carp size
  • How finicky the fish are

Quick HTML table for reference

html

<table>
  <tr>
    <th>Situation</th>
    <th>Recommended hook size</th>
  </tr>
  <tr>
    <td>Small carp (~10 lb), small bait (10–12 mm)</td>
    <td>Size 10–8</td>
  </tr>
  <tr>
    <td>Average carp (10–20 lb), 15–18 mm boilies</td>
    <td>Size 8–6</td>
  </tr>
  <tr>
    <td>Big carp (20–30 lb+), 20 mm+ boilies</td>
    <td>Size 6–4 (down to 2)</td>
  </tr>
  <tr>
    <td>Worm baits</td>
    <td>Size 8 for small pieces, 6–4 for whole worms</td>
  </tr>
</table>

TL;DR

If you just want one answer to start with: tie on a sharp size 6 or 8 carp hook with a 12–15 mm boilie on a hair rig and you’ll be well‑covered for most normal carp fishing situations.

Information gathered from public forums or data available on the internet and portrayed here.