Diffuser Wattage, Amps & Running Costs [Test Results Listed]

Last updated: February 6, 2024.

Electric devices that heat water (or air) are usually energy guzzlers. But is this the case for essential oil diffusers? Find out below & see how you can quickly reduce your electric bills & carbon footprint.

In this article you’ll find diffuser wattage details, see how many watts diffusers actually use (from a power consumption test), how much kWh of electricity they use per month, how much they cost to run and their impact on the average electric bill.

You’ll also see how many amps diffusers use and get diffuser voltage insights.


  • Essential oil diffusers are not energy guzzlers.
  • Diffusers can continue to use electricity when off but still plugged in.
  • Diffuser wattage / power rating is typically 12W and they commonly draw 0.5A.

Continue reading for more details, including how much diffusers cost per month to run, and see power consumption results from an energy monitoring test.

Just a quick note to avoid potential confusion: this article is about diffusers, more specifically oil diffusers / essential oil diffusers. These are also referred to as aroma diffusers, aromatherapy diffusers, essential oil humidifiers, scent diffusers, fragrance diffusers, electric diffusers and plugin diffusers. This article does not cover light diffusers, flash diffusers, HVAC diffusers, or other diffuser types. 

Diffuser Wattage, Amps and Running Costs Image containing a diffuser and text

Oil diffuser wattage

Oil diffusers are typically 12W.

Diffuser wattage ranges from 6W to 25W. However, there are some outliers but these are less common.

Amazon’s Choice for “essential oil diffuser” is 7.5W – 10W (check it out here).

Essential oil diffuser wattage refers to the power rating listed by the manufacturer. This is the maximum amount of watts that the device will use under normal operating conditions.

Diffusers don’t typically operate at its max power rating. The actual amount of power consumed by plug-in essential oil diffusers varies by mode.

Using an energy monitor, I put my diffuser to the test.

How many watts does a diffuser use (power consumption test)

A typical 12W diffuser consumes 0.43 watts in standby mode, 11.7 watts in On mode without lights, and 11.9 watts in On mode with LEDs on.

These figures are extrapolated from the following energy consumption test.

Using an energy monitor I tested how many watts my 7.5W AromaWorks diffuser consumes across different modes. Here are the results:

  • Power rating / listed wattage: 7.5W.
  • On standy: 0.27W – 3.6% of the listed wattage.
  • On: 7.32W – 97.6% of the listed wattage.
  • On with light (LED): 7.42W – 98.9% of the listed wattage.
Diffuser Power Consumption Test Results Image containing an outlet and screenshots of results for how many watts a diffuser actually uses

Essential oil diffusers can continue to use electricity when plugged in even if they aren’t in use. My AromaWorks diffuser consumes 0.27W in standby mode.

So be sure to unplug your essential oil diffuser to reduce energy wastage.

In On mode, without any lights turned on, my diffuser consumes 7.32W. This is 97.6% of the max wattage listed by the manufacturer.

Modern diffusers come equipped with LED lights, which slightly increase the amount of watts that the device consumes.

Switching the LED on while my diffuser is running adds 0.1W to the actual power consumption.

If you’re interested in monitoring the actual power consumption of your household appliances, check out the Kasa Smart Plug by TP-Link on Amazon here – this is the device I used to see how many watts my diffuser uses. It’s also a smart plug, which enables you to essentially turn any of your appliances into smart appliances.

I use it to get insights into the actual power consumption of my appliances and to make more informed decisions about my energy usage.

One key benefit for me is that it enables me to turn all my appliances off at night through an app. This helps keep my carbon footprint and electric bills low.

Check it out on Amazon, here, or Walmart, here, to reduce your bills and carbon footprint.

Next, let’s take a look at how much electricity, in kilowatt-hours (kWh), diffusers use over longer periods of time.

How much electricity does a diffuser use (in kWh)

A typical 12W diffuser uses 0.00043 kWh of electricity in standby mode per hour, 0.0117 kWh in On mode without lights, and 0.0119 kWh in On mode with LED lights on.

The maximum amount of electricity that a typical 12W diffuser can consume is 0.012 kWh per hour.

As mentioned, it’s common to find diffusers with power ratings ranging from 6W to 25W. Assuming max power consumption, these diffusers can consume between 0.006 kWh and 0.025 kWh of electricity per hour.

Using a typical 12W diffuser for 2 hours per day (with LEDs on) and leaving it plugged in for the remaining 22 hours, you can expect a diffuser to consume 0.0333 kWh of electricity per day.

But what about per month?

How much electricity does a diffuser use per month

A typical 12W essential oil diffuser will consume roughly 1.03 kWh of electricity per month.

This assumes 2 hours in On mode (with LEDs on too) per day and 22 hours in standby mode per day, for 31 days.

So is this a lot?

Do diffusers use a lot of electricity

No. Diffusers do not use a lot of electricity.

Usually, electric appliances that heat water (or air) consume a lot of electricity.

For example, electric kettles and space heaters are considered energy guzzlers.

Diffusers, however, do not fall into this category.

The typical power rating of diffusers ranges from 6W to 25W, with 12W being very common.

Electric kettles and space heaters can have power ratings over 10 times larger than diffusers.

To add more perspective, a typical 12W diffuser consumes:

For further perspective, US households consume 877 kWh of electricity per month, on average, according to the U.S. Energy Information Administration

And, as mentioned, using a typical diffuser for 1 month (2 hrs on p/d and continuously plugged in) consumes approx. 1.03 kWh of electricity. This means that:

Using an essential oil diffuser will increase household power consumption by approx. 0.1%, on average, per month.

So oil diffusers do not use a lot of electricity.

Next, let’s take a brief look at how much diffusers cost to run.

Cost to run a diffuser

A typical 12W diffuser costs $0.0000645 per hour in standby mode, $0.001755 per hour in On mode without lights, and $0.001785 per hour in On mode with LED lights on.

Assuming it runs at its max power rating, a typical diffuser will cost $0.0018 per hour.

These costs are based on the average price per kWh in the US: $0.15.

Essential oil diffusers cost a fraction of a cent to run per hour.

Per month, using the device for 2 hours in On mode (with LED lights on too) per day and leaving it continuously plugged in for the rest of the day, the costs do increase.

It costs just over 15 cents per month to run a typical 12W essential oil diffuser.

Let’s put these running costs into context…

Are diffusers expensive to run

Diffusers are not expensive to run.

A typical diffuser costs just over 15 cents per month, on average, which means that they account for just 0.13% of the average monthly US household electricity bill.

The average US monthly electricity bill is $115.

Next, let’s briefly cover some other power related topics, specifically diffuser voltage and amp draw.

Diffuser voltage

Essential oil diffusers are usually dual voltage, meaning they work with 110 and 240 volt supplies.

This basically means that you don’t need to worry about what supply voltage you have, in most cases at least.

For example, diffusers tend to work in the US (where 110V is most common) and in the UK (where they have a 230/240V supply) without the need for an inverter.

However, to be on the safe side you should buy a diffuser from a retailer in your country (they always, or at least almost always, sell the devices with correct specs) and then double check that the voltage is appropriate for your home.

Diffusers tend to convert 100-240V (50-60Hz) AC into 24V DC. This is usually done via the adapter (i.e. the power cord).

As a result, diffusers tend to be dual voltage because they are shipped with universal adapters.

A good example is this is the standout, high performing, well designed SPT Ultrasonic Essential Oil Diffuser on Best Buy – check it out here.

How many amps does a diffuser use

Diffusers commonly draw 0.5A.

It’s also common to see oil diffusers that pull 0.35A and 1A.

Current draw is quite low for oil diffusers.

Diffuser amperage is usually listed on the underside of the device. As you can see from the image below, my diffuser draws 350mA. In other words, it pulls 0.35A.

How Amps Does A Diffuser Use Image of the underside of a diffuser which lists the amps, voltage and wattage of the device

Final thoughts

At this point in articles, I usually list ways that you can reduce the cost of using the device in question. However, given that the power consumption is surprisingly low for essential oil diffusers, I won’t in this case.

Instead, below is a resource for more impactful methods of reducing your electric bills and carbon footprint.

Get the 6 Quick Wins cheat sheet here: