# How Does Strava Calculate Watts?

Strava calculates watts by measuring your speed and the amount of time it takes you to complete a certain distance.

If you’ve ever wondered how Strava calculates your watts, you’re not alone. The truth is, there’s no one definitive answer.

There are a few different ways to measure wattage, and each has its own advantages and disadvantages. The most common way to calculate watts is to use a power meter. This measures the actual amount of power that you’re putting out.

However, power meters can be expensive, and they’re not always accurate. Another option is to use a heart rate monitor. This can give you a good idea of how hard you’re working, but it’s not as accurate as a power meter.

The last option is to use Strava’s own estimation. This isn’t as accurate as a power meter or a heart rate monitor, but it’s a good way to get an idea of your wattage.

So, how does Strava calculate watts? The answer is that it depends on the method that you’re using. If you’re using a power meter, it’s more accurate than if you’re using a heart rate monitor. And if you’re using Strava’s estimation, it’s not as accurate as either of those methods, but it’s still a good way to get an idea of your wattage.

## How Does Strava Calculate Average Power?

Strava calculates average power by taking the average of the power output of a user over a set period of time.

There’s a lot that goes into calculating your average power on Strava, but we’ve got the breakdown so you can understand exactly how it works.

Your average power is calculated by taking the total power output of your ride and dividing it by the duration of the ride. Power is measured in watts and is a measure of the work you’re doing on the bike. The more power you’re outputting, the harder you’re working.

To get your average power, Strava takes the power readings from your device (watts) and multiplied by the duration of the ride (seconds), then it divides that by the ride’s duration in minutes.

For example, let’s say you went for a one-hour ride and your power meter recorded that you averaged 200 watts. Here’s how Strava would calculate your average power.

200 watts x 60 seconds x 1 hour = 72,000 watt seconds

72,000 watt seconds / 60 minutes = 1,200 watts

Your average power for that ride was 1,200 watts.

Now that you know how Strava calculates your average power, you can use that information to train more effectively. Aim to increase your average power over time by putting in more power on rides and cutting down on ride duration. As your average power goes up, so will your Strava ranking!

## How Does Strava Calculate Normalized Power?

Strava calculates normalized power by taking an athlete’s power output data and correcting it for variability.

Normalized power is a measure of your average power output over a period of time, typically 20 minutes. Your Normalized Power® (NP®) score is calculated by Strava using an algorithm that smooths out the variability in your power data, making it easier to see your true average effort.

Here’s how it works: first, we take your power data and calculate your moving average power for every second of your activity. Then, we apply a mathematical model that identifies and filters out the effects of short-term variability (like hills, wind, etc.), resulting in a more accurate representation of your average power.

This number is your NP® score, and it’s a great way to compare efforts of different duration and intensity. For example, you can use your NP® score to compare a hilly 30-minute tempo ride with a flatter 60-minute endurance ride, or a hard interval workout with an easy recovery ride.

To calculate your NP® score, all you need is a power meter. If you don’t have one, don’t worry – you can still use Strava to track and compare your efforts. We’ll use your heart rate data to estimate your power and calculate your NP® score.

### FAQ

#### How Does Strava Calculate Intensity Factor?

Strava’s intensity factor is a number that is meant to represent how hard a given activity is. It is calculated using data from a variety of sources, including heart rate, speed, and elevation.

#### How Does Strava Calculate Training Stress Score?

The Training Stress Score® (TSS®) is a metric developed by Dr. Andrew Coggan and Allen Lim in “Training and Racing with a Power Meter” to measure the intensity and duration of a ride and quantify the overall stress placed on the rider. TSS is calculated by multiplying the average power of the ride by the duration of the ride and then dividing by 1000.