Ω How to Read Ohms on a Multimeter

Ohms (Ω) are a unit of electrical resistance—used to tell you how much a component resists the flow of electricity. Measuring ohms with a digital multimeter is an essential skill for diagnosing circuits, checking resistors, and troubleshooting electronics.

In this guide, we’ll show you how to read ohms like a pro using a digital multimeter.

📖 What Is an Ohm?

The ohm (Ω) measures resistance. One ohm means that one volt is needed to push one amp through a circuit.
Higher resistance = harder for electricity to flow.

🧪 When Do You Need to Measure Resistance?

• Check if a resistor is working properly

• Identify broken wires or poor connections

• Test coils, fuses, switches, and heating elements

• Verify PCB traces or circuit board components

🔧 What You’ll Need

• A digital multimeter with resistance mode (Ω)

• Test probes

• The component or wire to test

• Optional: color code chart for resistors

👉 Tip: BSIDE models like the S30, SH7, or S11 are perfect for resistance testing.

📏 How to Read Ohms in 5 Easy Steps

Step 1: Turn Off the Power

Never measure resistance in a live circuit—this can damage your meter and produce incorrect readings.

Step 2: Set the Multimeter to Resistance (Ω)

Turn the dial to the Ω symbol.
If you're using a manual-ranging multimeter, choose the expected range:

• 200Ω / 2k / 20k / 200k / 2M / etc.
  Auto-ranging meters will do this for you.

Step 3: Zero the Meter (Optional)

Touch the two probes together.
You should get a reading close to 0.0Ω, indicating proper connection.
This ensures your meter isn’t reading internal resistance from the leads.

Step 4: Connect Probes to the Component

Touch one probe to each end of the component (resistor, wire, etc.).

What you may see:

Step 5: Interpret the Result

• Compare your reading to the expected value (e.g., from a resistor color code or circuit diagram).

• Read the unit carefully:

  • 1.0 = 1 ohm

  • 1k = 1000 ohms

  • 1M = 1,000,000 ohms

💡 Real-World Example

Let’s say you’re testing a 220Ω resistor:

• Your multimeter shows 218.4Ω

• ✅ That’s within the ±5% tolerance range (expected for carbon film resistors)

But if it showed OL, that means the resistor is likely burnt or open-circuit.

⚠️ Common Mistakes to Avoid

• Testing while powered on

• Misreading the unit (Ω vs kΩ vs MΩ)

• Touching the metal probe tips with your fingers (adds body resistance)

• Expecting 100% accuracy—most resistors have ±5% or ±1% tolerance

🔧 Why Use a BSIDE Multimeter?

BSIDE multimeters are designed with:

✅ Auto-ranging and manual Ω modes
✅ Backlit screen for readability
✅ Fast response and stable resistance detection
✅ Audible continuity + resistance testing in one mode

Perfect for electronics hobbyists, HVAC technicians, and repair professionals.

✅ Conclusion

Reading ohms with a multimeter is simple once you understand the symbol, steps, and expected values.
With just a few tests, you’ll be able to troubleshoot circuits, confirm resistor values, and verify components like a pro.