Watt-Seconds to Calories Converter

Enter the energy in watt-seconds below to get the value converted to calories.


Result in Calories:

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1 Ws = 0.239006 cal

Do you want to convert calories to watt-seconds?

How to Convert Watt-Seconds to Calories

To convert a measurement in watt-seconds to a measurement in calories, multiply the energy by the following conversion ratio: 0.239006 calories/watt-second.

Since one watt-second is equal to 0.239006 calories, you can use this simple formula to convert:

calories = watt-seconds × 0.239006

The energy in calories is equal to the energy in watt-seconds multiplied by 0.239006.

For example, here's how to convert 5 watt-seconds to calories using the formula above.
calories = (5 Ws × 0.239006) = 1.195029 cal

How Many Calories Are in a Watt-Second?

There are 0.239006 calories in a watt-second, which is why we use this value in the formula above.

1 Ws = 0.239006 cal

Watt-seconds and calories are both units used to measure energy. Keep reading to learn more about each unit of measure.

What Is a Watt-Second?

The watt-second is a measure of electrical energy equal to one watt of power over a one second period. One watt-second is equal to 1/3,600 of a watt-hour or one joule.

Watt-seconds are usually abbreviated as Ws, although the formally adopted expression is W·s. The abbreviation W s is also sometimes used. For example, 1 watt-second can be written as 1 Ws, 1 W·s, or 1 W s.

In formal expressions, the centered dot (·) or space is used to separate units used to indicate multiplication in an expression and to avoid conflicting prefixes being misinterpreted as a unit symbol.[1]

Learn more about watt-seconds.

What Is a Calorie?

One calorie is equal to the heat needed to raise the temperature of one gram of water from 14.5 to 15.5 degrees Celsius.

When measuring the energy content in foods, the large calorie, or kilocalorie is used, but it's often still just called a "calorie." When both the calorie and large calorie are used in the same context it is common to refer to the calorie as a "small calorie."

Calories can be abbreviated as cal; for example, 1 calorie can be written as 1 cal.

Learn more about calories.

Watt-Second to Calorie Conversion Table

Table showing various watt-second measurements converted to calories.
Watt-seconds Calories
1 Ws 0.239006 cal
2 Ws 0.478011 cal
3 Ws 0.717017 cal
4 Ws 0.956023 cal
5 Ws 1.195 cal
6 Ws 1.434 cal
7 Ws 1.673 cal
8 Ws 1.912 cal
9 Ws 2.1511 cal
10 Ws 2.3901 cal
11 Ws 2.6291 cal
12 Ws 2.8681 cal
13 Ws 3.1071 cal
14 Ws 3.3461 cal
15 Ws 3.5851 cal
16 Ws 3.8241 cal
17 Ws 4.0631 cal
18 Ws 4.3021 cal
19 Ws 4.5411 cal
20 Ws 4.7801 cal
21 Ws 5.0191 cal
22 Ws 5.2581 cal
23 Ws 5.4971 cal
24 Ws 5.7361 cal
25 Ws 5.9751 cal
26 Ws 6.2141 cal
27 Ws 6.4532 cal
28 Ws 6.6922 cal
29 Ws 6.9312 cal
30 Ws 7.1702 cal
31 Ws 7.4092 cal
32 Ws 7.6482 cal
33 Ws 7.8872 cal
34 Ws 8.1262 cal
35 Ws 8.3652 cal
36 Ws 8.6042 cal
37 Ws 8.8432 cal
38 Ws 9.0822 cal
39 Ws 9.3212 cal
40 Ws 9.5602 cal


  1. Bureau International des Poids et Mesures, The International System of Units (SI), 9th edition, 2019, https://www.bipm.org/documents/20126/41483022/SI-Brochure-9-EN.pdf

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