Work out the CO2e of a regular commute by transport mode, per week and per year, using UK DEFRA conversion factors.
Commute Emissions Calculator does its work in front of you rather than sending anything away to be processed. What you see is the whole of it.
Your input goes into a function and the result comes back out, both inside this tab. There is no round trip and no third party in the middle.
You will find it under Environment, alongside 6 other tools for the same sort of job.
Runs in this tab, so nothing you type is uploaded.
distanceKm: 15 mode: car daysPerWeek: 5
Weekly distance km: 150 Weekly kg: 25.5 Yearly kg: 1224 Yearly tonnes: 1.22 Car kg if driven: 1224 Saving vs car kg: 0
Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.
No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.
Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.
Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.
Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.