Blood Knot

Difficulty: Medium
Strength: High

Best Used For

Line to LineSimilar DiameterFly Fishing

One of the best knots for joining two lines of similar diameter. Popular in fly fishing.

About the Blood Knot

The Blood Knot is considered the gold standard for joining two lines of similar diameter. This elegant knot creates a strong, streamlined connection that's particularly valued in fly fishing for building tapered leaders. While it requires more skill to tie than simpler knots, its superior strength and neat appearance make it worth mastering.

Best Line Types: Lines of similar diameter - monofilament to monofilament, fluorocarbon to fluorocarbon

Knot Strength: Retains 85-95% of the line's original strength

When to Use: Perfect for building tapered leaders, joining tippet sections, and any situation where you need a strong, streamlined connection between similar lines.

Step-by-Step Instructions

  1. Overlap lines: Overlap the two lines by about 6 inches.
  2. Wrap first line: Wrap one line around the other 5-7 times.
  3. Thread through center: Pass the tag end back through the center opening between the lines.
  4. Wrap second line: Wrap the other line around the first line 5-7 times in the opposite direction.
  5. Thread second end: Pass this tag end through the center opening in the opposite direction from the first.
  6. Wet and tighten: Moisten the knot and pull both standing lines slowly to tighten.

Pro Tips & Troubleshooting

✓ Pro Tips

  • • Best for lines within 2x diameter difference
  • • Essential knot for fly fishing leaders
  • • Creates the strongest line-to-line connection
  • • Use fewer wraps (5) for thicker lines
  • • Practice with different colored lines to see structure

⚠ Common Mistakes

  • • Using with lines too different in diameter
  • • Not keeping wraps tight and neat
  • • Threading tag ends in same direction
  • • Pulling too hard too fast when tightening
  • • Not wetting the knot before final tightening

Video Tutorial

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