Tools & Resources

Wire Marker Sizing Calculator

Find the right heatshrink, non-shrink, or 2-part wire marker for your cable. Enter the overall outer diameter (OD) to see compatible options instantly.

TL;DR

Enter the overall outer diameter (OD) of your wire – including insulation – to see which marker types and sizes are compatible. Heatshrink markers offer the widest range as they shrink down to fit, while non-shrink and 2-part markers require more precise sizing.

1

Enter your wire diameter

Input the overall outer diameter (OD) of your wire or cable – this is the full diameter including the insulation jacket, not just the conductor cores. If you're marking over a connector, also enter the connector diameter below.

Wire Marker Sizing Calculator

Measure the Overall Diameter (OD)
Include the outer insulation jacket – not just the conductor cores

Enter the full outer diameter of your cable, including all insulation layers.

If using heatshrink, the marker must pass over any connectors before shrinking. Non-shrink markers cannot pass over connectors larger than the wire.

Compatible Wire Markers

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Your Wire Specification

Enter a diameter to see compatible markers

Heatshrink Markers
LSZH (2:1) & Premium (3:1) shrink ratios
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Compatible Sizes
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Heatshrink markers can pass over connectors before being heated, then shrink down to grip the wire.
Available Products
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Non-Shrink Markers
Fixed size range, no heat required
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Compatible Sizes
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Non-shrink markers cannot pass over connectors larger than the marker's internal diameter.
Available Products
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2-Part System
Tubing + printed insert, slides on before termination
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Compatible Sizes
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Tubing (e.g. LT/1-2) slides onto wire before termination. Labels (L8/20T, L8/30T, L8/50T) insert into tubing at any time.
Available Products
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Quick Comparison for Your Wire Size
Feature Heatshrink Non-Shrink 2-Part
Heat gun required ✓ Yes ✗ No ✗ No
Install after termination ✓ Yes ✗ No ✗ No
Permanent fit ✓ Yes ✓ Yes ✗ Removable
Ideal for Retrofit & permanent Fast installation Flexible / changes

Tip: If you have connectors already fitted, heatshrink can slide over the connector before shrinking. Non-shrink and 2-part markers must be installed before termination.

2

Understanding marker types

Each marker type has different characteristics that make it suitable for different applications. Here's what you need to know:

Heatshrink

Shrinks when heated for a permanent, secure fit. Polyolefin material.

  • ◆ LSZH: 2:1 ratio, halogen-free
  • ● Premium: 3:1 ratio, 90°C shrink
  • Ladder (L25/L50) or Roll (R) format
  • Roll format requires LGS3

Non-Shrink

Figure-of-8 grip design, 25× faster than ferrules. No heat required.

  • Legend™: PVC material
  • Fox-Flo®: LSZH, UV stable
  • Continuous roll, requires LGS3
  • Must slide on before termination

2-Part System

Clear PVC tubing + printed polypropylene insert. Label changeable after termination.

  • Tubing slides on before termination
  • Labels: L8/20T, L8/30T, L8/50T
  • Tubing sizes: 1-2 to 10-14mm
  • Thermal or Laser printable

Ready to order your wire markers?

Browse our full range of heatshrink, non-shrink, and 2-part wire marking solutions.

Browse Wire Markers Labelling Cheat Sheet
Disclaimer: The sizing recommendations provided by this calculator are for guidance only. Always verify marker compatibility with your specific wire and installation requirements. Actual fit may vary depending on wire insulation material and thickness. For critical applications, we recommend testing before bulk ordering. E&OE.