Air quality, carbon, plastic and UV, worked out from published methods
These free calculators put numbers on everyday environmental questions. The AQI calculator turns pollutant readings into India’s National Air Quality Index or the US EPA AQI, with the health advice for each band, and the UV burn time calculator estimates how quickly skin may redden at a given UV index.
The tree carbon offset calculator estimates how many trees it takes to absorb an amount of CO₂, as a range from IPCC growth data, and the plastic footprint calculator adds up a household’s single-use plastic in kilograms a year, with ideas to cut it.
Where the numbers come from
- Published methods. AQI uses the CPCB National Air Quality Index report and the US EPA technical guide, tree growth uses the IPCC guidelines, and UV uses the WHO Global Solar UV Index guide.
- Estimates are labelled. Tree absorption, plastic weights and burn times vary a lot in real life, so the pages show ranges and say what is assumed.
Related tools elsewhere on the site
- Carbon and water. The carbon footprint calculator and rainwater harvesting calculator are in home and DIY, and the flight carbon footprint calculator is in travel.
Environment & Climate: frequently asked questions
Is the AQI here the same as the official AQI?
It uses the official formulas, but the official AQI is based on averages from monitoring stations. Use the calculator to understand readings, and the CPCB or your local agency for official values.
Does planting trees cancel my emissions?
Not straight away. A young tree absorbs little for its first years and may not survive. Cutting emissions comes first, and the tree calculator shows how long offsets take.
Is the UV burn time safe to rely on?
No. The WHO advises against relying on burn times. Protect your skin whenever the UV index is 3 or higher; the calculator is for understanding, not for planning time in the sun.