Plastic Footprint Calculator

Estimate your annual single-use plastic footprint in kilograms from bottles, bags, food packaging, cups, and cutlery used per week, with a per-item breakdown and practical alternatives to reduce it.

By Marshkalk

Enter how many of each single-use plastic item you use in a typical week to get an estimate of your yearly plastic footprint in kilograms, broken down by item type.

A standard 500 mL PET bottle with its cap weighs about 25 g.

A thin single-use carrier or produce bag weighs about 7 g.

Ready-meal trays, wrapped produce, and film lids, about 12 g each on average.

A takeaway cup with its lid, about 9 g of plastic even when the cup itself is lined paperboard.

A single straw, fork, or stirrer weighs about 4 g.

Anything else disposable: sachets, blister packs, wrapping, about 10 g each on average.

What single-use plastic actually weighs

Most people underestimate their plastic footprint because they think in items, not weight. A bottled water habit of one bottle a day adds up to roughly 9 kg of PET plastic a year on its own, and once food packaging, cups, and bags are added in, a fairly ordinary week of habits can reach 30 to 50 kg of single-use plastic a year. This calculator uses average item weights for bottles, bags, packaging, cups, and cutlery to convert a weekly habit into an annual total, then breaks it down by category so you can see which habit weighs the most.

Average item weights used in this estimate

ItemApproximate weight
500 mL PET bottle with cap25 g
Thin single-use carrier or produce bag7 g
Food packaging item (tray, film, wrap)12 g
Disposable cup with lid9 g
Straw, cutlery item, or stirrer4 g
Other single-use item (sachet, blister pack)10 g

Plastic bag rules and packaging waste in the UK

England introduced a 5p charge on single-use plastic carrier bags in 2015, raised to 10p in 2021, which cut supermarket bag use by well over 90% according to government figures, though thinner "bags for life" have since taken some of their place. Since October 2023 England has also banned single-use plastic cutlery, plates, and expanded polystyrene cups and trays for food outlets, which is why the cutlery and cups you still use are increasingly likely to be reusable or non-plastic in shops and cafes. Estimates of UK household single-use plastic packaging place the average person at somewhere around 35 to 45 kg a year, which is the range this tool compares your total against.

What this calculator cannot do

The weights above are averages: a heavy glass-effect shampoo bottle or a padded courier bag weighs far more than a thin produce bag, and this tool has no way to know the exact packaging format you use. It also does not cover plastic in clothing, furniture, or electronics, only the disposable, short-lived items people go through week to week. Treat the total as a way to compare habits and spot the biggest contributor, not as a certified waste audit.

Where the biggest cuts usually come from

For most people, bottled water is the easiest big win: a refillable bottle and a tap or filter jug removes an entire category at close to zero cost. After that, food packaging tends to be the largest remaining share, so buying loose produce, choosing bulkier packs over multiple small ones, and using a refill shop where available typically cuts more weight than swapping straws or cutlery, even though those are the items people notice first. For a wider view of your environmental habits alongside plastic, the Carbon Footprint Estimator covers transport, heating, and diet in the same style.