What is Plastic Footprint Calculator?
Plastic Footprint Calculator helps you estimate annual plastic weight from weekly item use and item weights.
The main result is annual plastic use, with a breakdown of potential annual reduction and remaining annual use. The formula, example and assumptions below explain how to interpret it.
How to use Plastic Footprint Calculator
Use the example to get familiar with the form, then enter your own figures. Any rates in the example are illustrative. Check the field labels and units before calculating.
- Gather plastic items used per week, average plastic weight per item (g) and planned reduction (%). Use values from the same situation or reporting period.
- Replace the example plastic items used per week with your own value, then complete the other fields. Check the displayed units.
- Select Calculate and read annual plastic use with its result breakdown. Change one input and calculate again to compare a second scenario. Reset restores the original example.
- Enter plastic items used per week, at least 0 and at most 100000. Use a whole number.
- Enter average plastic weight per item in g, at least 0. Decimals are accepted.
- Enter planned reduction in %, at least 0 and at most 100. Decimals are accepted.
Plastic Footprint Calculator: a worked example
With the inputs below, the result is 15.6 kg (annual plastic use). Follow the example, then replace these illustrative values with your own.
| Input or output | Example value |
|---|---|
| Plastic items used per week | 20 |
| Average plastic weight per item (g) | 15 g |
| Planned reduction (%) | 50 % |
| Annual plastic use | 15.6 kg |
| Potential annual reduction | 7.8 kg |
| Remaining annual use | 7.8 kg |
Understanding the Plastic Footprint result
Read annual plastic use alongside potential annual reduction and remaining annual use. These describe different parts of the same calculation.
Displayed results use a readable number of decimal places. When checking a result by hand, keep extra precision until the last step. To compare scenarios, change one input at a time and keep the others fixed.
- Example Potential annual reduction: 7.8 kg
- Example Remaining annual use: 7.8 kg
Plastic Footprint Calculator: assumptions and common mistakes
A useful estimate starts with the right inputs. Check the following assumptions and limits before applying the result to your situation.
- Match factors to your location and reporting period. A result covers the sources you entered, not an independently verified full footprint.
For wider guidance, visit GHG Protocol calculation guidance. The formula and scope of this specific tool are stated on this page.
