How to Find Your Doorbell’s Voltage

If you’re planning to install a smart doorbell or replace your existing one, one of the first things you need to know is what voltage your doorbell system uses. Most doorbells in the U.S. run on low voltage (usually 16-24V), but it’s important to be sure before buying or installing anything.

✅ 1. Check the Doorbell Transformer (Most Reliable)

• Your doorbell system runs through a transformer, which lowers your home’s high voltage (120V) down to the low voltage needed for the doorbell.
• Find the transformer — it’s usually located near:
  • Your electrical panel
  • In the basement or attic
  • Inside a junction box near the chime or doorbell
• Once found, look at the label on the transformer. It will usually say something like:
  Output: 16V 10VA

✅ 2. Use a Multimeter (If You Can’t Find the Label)

• If the label is missing or hard to read, you can test the voltage directly using a multimeter.
• Steps:
  1. Set your multimeter to AC voltage.
  2. Place the two probes on the screws of the transformer or across the wires connected to the doorbell or chime.
  3. Read the number — it will likely show something like 16V, 18V, or 24V.

⚠️ Safety tip: Be cautious when using a multimeter. If you’re unsure, ask someone with electrical experience for help.

✅ 3. Check the Chime Box or Doorbell Wires

• Sometimes, the voltage is printed inside the chime box or even near the doorbell button.
• If you’re replacing an old doorbell, check the wiring — low-voltage wires are usually thin and color-coded (red, white, etc.).

✅ 4. Search Online with Model Number

• If your transformer or chime has a model number, you can search it online to find the voltage rating.
• This is useful if the label is faded or missing.

✅ 5. Ask or Test (if Renting or Unsure)

• If you’re in a rented property or can’t access the transformer, try:
  • Asking your landlord or property manager.
  • Contacting the builder or electrician if it’s a new home.

🛠 Common Doorbell Voltages

🧠 Final Tip

Always check the requirements of your smart doorbell (like Ring or Blink) — they often need a minimum voltage and power (VA) to work properly. Undervoltage may cause them to malfunction or not work at all.