One kilogram of plastic is equivalent to 50 single-use 500 ml plastic bottles, based on our Bottle2KG research study across more than 100 collection branches in the Philippines and Indonesia.
How many plastic bottles are in a kilogram?
One kilogram of plastic is equivalent to 50 single-use 500 ml plastic bottles, based on our Bottle2KG research study across more than 100 collection branches in the Philippines and Indonesia.
Watch the video
Fifty, not fifty-six.
The study measured a weighted average of 56.39 bottles per kilogram. We report 50, so the impact we claim on behalf of our members is always less than the impact they funded.
- 50
- bottles per kilogram, as published
- 56.39
- bottles per kilogram, as measured
- 100+
- collection branches sampled
Watch the study.
Plastic Bank conducted a Bottle to Kilogram Research Project to evaluate our metric and arrive at a standardization on the number of plastic bottles in one kilogram of plastic materials, using various parameters. The study provides empirical evidence for the number of bottles in a kilogram and improves the transparency of our impact claims.
Results by country.
Bottle weight varies with the brands and formats common in each market, so the study reports each country separately before weighting them into one figure.
| Country | Collection branches sampled | Bottles per kilogram |
|---|---|---|
| Indonesia | 58 | 53.08 |
| Philippines | 44 | 59.69 |
| Both countries | 102 | 56.39 |
Plastic Bank reports 50 bottles per kilogram — the measured average rounded down, so that every impact figure we publish understates rather than overstates the result.
How the study was run.
Collected plastic was counted and weighed at more than 100 collection branches across the Philippines and Indonesia. Each branch recorded the number of small PET bottles (350–600 ml, the most commonly available sizes during collections) that made up a kilogram of collected material, and the country figures are the averages of those records.
- Method
- Counted and weighed at the branch
- Coverage
- 100+ branches, 2 countries
- Published
- 8 May 2023
Common questions
The measured weighted average across both countries is 56.39 bottles per kilogram. We round down to 50 so that the impact reported to members and partners is never overstated.
The study counted small PET bottles of 350 ml and 600 ml — the most commonly available sizes during collections. Our published claim uses 500 ml as a representative single-use bottle size.
Yes. Branches in Indonesia averaged 53.08 bottles per kilogram and branches in the Philippines averaged 59.69. Bottle weight varies with the brands and formats common in each market.
Collected plastic was counted and weighed at more than 100 collection branches across the Philippines and Indonesia, and the results were averaged by country and then weighted into a single figure.
Multiply your kilograms by 50. A member who has funded the collection of 20 kilograms of plastic has stopped the equivalent of 1,000 single-use bottles from reaching the ocean.