How Many Watts is a Laptop?

how many watts is a laptopBefore you gauge the power efficiency of your laptop, it is common to ask how many watts is a laptop.

The wattage rating of the laptop differs significantly from model to model. A simple laptop with an Atom processor will have a minimum power rating; whereas, a gaming laptop can be substantially demanding.

Although it is important to know how many watts is a laptop, it is important to realize that there is a difference between power rating and consumption.

Let us recap this concept a bit.

Maximum Power Rating

The easiest way to answer how many watts is a laptop is to look at its maximum power rating.

Depending on the make, model, type, and size of the laptop, the maximum power rating can range from 20W to 250W. For some models, it could be even higher. However, if you are comparing this with a high-end PC, it is still significantly low.

Finding out the Power Rating of your laptop is quite simple. The power rating is always mentioned on the power adapter. It is either explicitly mentioned in watts, or the rating of Voltage and Amperes are provided.

Note that power adapters have different Voltage (V) and Amperage (A) ratings for input and output.

To learn the power rating of your laptop, you need to take note of the “output” ratings. Once you have output voltage and amperes rating, you simply multiply them both to get the power rating. (Voltage x Amperes = Power)

Example of Maximum Power Rating
For example, my laptop which has a Core i5 processor along with 8 GB of RAM, 15.6″ Touchscreen, 500 GB HDD, and no graphics card has the rating of 19.5 Volts and 2.31 Amperes. This equates to 45 Watts.

As another example, have a look at this:

how many ghz do i need

Whichever laptop this adapter belongs to has got to be a high-end one. The laptop has an output voltage of 19.5 V and amperage of 10.3 A. As a result; it has a maximum power rating of 200W. This is quite significant.

What Does This Mean?

The maximum power rating of 200W implies that all the components combined will consume 200 watts in an hour if used on maximum potential.

Most of the times, the laptop never reaches its maximum power rating. For example, in idle states or when doing low-key work, the laptop would be consuming half as much power or even less.

Watts (Rated Power) vs. Watt-hour (Consumption)

Instead of asking how many watts is a laptop, it is more feasible to ask how much is your energy consumption rate.

This is electricity 101.

Many people tend to get confused between the idea of Watts vs Watt-hour.

The former implies the maximum power the laptop can consume in an hour, the later means how the laptop is being used.

A watt-hour is the amount of energy used in a particular time period, whereas rated power is the instantaneous rate at which energy is being consumed. Energy consumption is represented in kilowatt hours (Wh). The rated power is measured in watts (W).

Example of Power and Consumption Comparison

The difference between the two parameters can be explained through an example. Suppose one 65 watt laptop is operated for 10 hours in a day for high demanding tasks. It would consume 650 watt-hours (Wh), assuming it works on maximum potential. Its demand would be 65 watts throughout the time period it is kept on.

Now if you operate the same 65 Watt laptop, but for low demanding tasks. It would consume must less power.

Therefore, even if you have a 250 Watt gaming laptop, it would be consuming less than half its rated power if you are using it for tasks like word processing, etc.

In short, your laptop’s energy bill will be reflective of how you use it.

Real-Time Monitor of Power Consumption

The only way to know how much power your laptop is consuming is to have a real-time power consumption monitoring interface. There are two ways that this can be achieved. You can either install software or get hardware that plugs into the wall socket.

With a Software

Using a software does not guarantee precise measurements. Furthermore, it is tough to calibrate the software on the machines if you do not know the exact hardware components.

One of the best software for measuring the power consumption of a computer is Microsoft Joulemeter. This is a pretty simple desktop app that you can install for free. Unfortunately, calibrating it could prove to be a hassle. Although on laptops the process is relatively easy and automated, the data it provides is only an estimate.

Helpful tool to estimate the power draw of system and components if you have no idea what that might be. Needs more input to be more accurate. –

how many watts is a laptop

To get a precise measurement of your laptop’s power consumption, you need to get an electricity monitor.

With Electricity Usage Monitor Device

how many watts is a laptopElectricity usage monitors are simple and inexpensive devices that plug into your wall socket to measure the power consumption of any devices they are connected to. They can provide you with accurate real-time power consumption data.

You can not only check the power consumption of your laptop at idle state but also in various scenarios.

P4400 by P3 is an example of one f the best electricity usage monitors in the market.

You can use this small, compact, and inexpensive device to measure consumption of all of your household appliances. It goes beyond just measuring the consumption. It can also calculate the expenses by the day, week, month, or even a year.

How many watts is a typical laptop for programming

A typical programming laptop harbors an Intel Core i5, along with 8 GB of RAM and an SSD. Given this configuration, you can expect the maximum power rating of the laptop to be in the range of 50W. If you get a smaller screened laptop i.e. 13.3″ or 14″ laptops, the power rating would be even lower.

If you get a laptop for game development, then you will be looking at a laptop that is not too different from a high-end gaming laptop. This would have a power rating of 200 – 250 Watts typically.


So to wrap-up the answer to the question: how many watts is a laptop, it depends on your perspective.

If you are asking the question about the maximum power rating, then it depends on the size and the hardware configuration. However, if you are asking the question about the power consumption, it depends on your use.

The maximum power rating can easily be figured out by having a look at the laptops spec sheet or the back side of the power adapter.

The answer to the question about consumption is a bit tricky. The most precise way to know the power consumption is to get an electricity usage monitor.