How to Measure a Euro Cylinder Lock

HOW TO MEASURE A EURO CYLINDER LOCK

Before ordering a new lock, it’s essential to measure your euro cylinder correctly. This quick guide will show you how to take accurate measurements to ensure the perfect fit for your door.

🧰 TOOLS YOU’LL NEED

  • 📏 Measuring tape or ruler
  • 🔑 Flathead screwdriver
  • 🪛 Phillips screwdriver
  • ⚙️ Your existing euro cylinder lock
  • 🧤 Safety gloves (optional)

🔧 STEP-BY-STEP GUIDE

1️⃣ Remove the Cylinder from the Door

Open your door and locate the long fixing screw on the edge (level with the keyhole). Unscrew it completely, then insert your key and turn slightly to release the lock cam. Pull the cylinder out gently.

2️⃣ Measure from the Centre of the Screw Hole

With the cylinder removed, measure from the centre of the screw hole to each end. You’ll have two measurements — the internal side and external side.

3️⃣ Record Both Sides Separately

For example, a 40/50 cylinder means 40mm on the inside and 50mm on the outside. Always measure both sides as they are not always equal.

4️⃣ Check the Overall Length

Add both measurements together to get the total cylinder length. This ensures your new lock will sit flush with the handle on both sides.

5️⃣ Double-Check Before Ordering

Compare your measurements to the product specifications. It’s better to remeasure twice than order the wrong size!

💡 Pro Tip: When in doubt, bring your old cylinder to compare directly, or upload a photo and we’ll help identify it for you.

✅ NEED HELP IDENTIFYING YOUR LOCK SIZE?

Upload a photo of your existing lock and we’ll confirm the correct replacement for you within 24 hours.

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