How it works

Getting there

How much your trip emits depends mostly on how far you go and how you get there:

• San Francisco (SFO) ↔ Newark (EWR) roundtrip, economy, nonstop: about 900 kg CO2e (all the gases combined, counted as carbon dioxide)
• Orange County ↔ SoFi Stadium, driving, roundtrip: about 22 kg CO2e

Flights count extra, because contrails and other effects at cruising altitude add warming beyond the carbon dioxide itself. Across all attendees, fan travel makes up 62% of US live-music emissions (77% in the UK), according to a December 2025 MIT Climate Machine study.

These are estimates, based on distance and how you travel.

Why it matters

Carbon dioxide stays in the air for a century or more, so what we add keeps adding up. CO2e (carbon dioxide equivalent) puts all the greenhouse gases on one scale, since some trap more heat than others.

Carbon credits

A carbon credit is a certificate a project earns for each tonne (1,000 kg) of CO2e it keeps out of the atmosphere or removes from it. You may have heard them called carbon offsets. An independent verifier checks the work before a registry issues the credit, a bit like getting a college credit for finishing a course. Unlike a college credit, it can be bought and sold until someone retires it, and after that no one else can claim it.

What they don't do

A carbon credit isn't a molecule-for-molecule undo of your trip. It represents a tonne kept out of the air or removed from it somewhere else, at a different time, so buying credits doesn't make your trip carbon neutral. It's a way to take responsibility for emissions that already happened, after reducing what you can.

What your money buys right now

Carbon credits fall into two main groups. Some avoid or reduce emissions, keeping new greenhouse gases out of the air. Others remove carbon that's already in the air and store it. We buy both.

Right now, about 96% of each purchase comes from Tradewater and 4% from Vaulted Deep.

How Thrivedom works

1. 1

   Your trip

   Tell us where you went and how you got there. We estimate its emissions from the distance and how you traveled, using emission factors from the UK government (DEFRA). Where DEFRA doesn't cover a way of traveling, like RVs or charter flights, we add assumptions of our own and show them with your estimate.

   How we estimate your trip →
2. 2

   See what it costs

   The price is set per kg of CO2e and includes our service fee, plus a small flat fee on small orders, so you see the full amount before you pay. You don't need an account to see it.

   How pricing works →
3. 3

   Buy carbon credits

   You buy credits equal to your trip's estimated emissions. You'll create an account when you buy, so your receipts have a home. Your receipt arrives right away, and your purchase appears on our public ledger, without your name. Changed your mind? You can cancel within 14 days and get back everything you paid.

4. 4

   Matched and retired

   We buy credits in whole tonnes ahead of time and retire them on their public registries, which can take up to about a month. Your purchase is matched to tonnes we've already bought. If we've used up that stock, it's matched to the next tonne we buy, which can take a little while. Your receipt and our ledger show the registry serial numbers of the tonnes your credits came from, once those tonnes are retired.

Want to do more? You can also chip in to a community pool that funds carbon credits for other fans' trips.

The science, if you're curious

Most transportation runs on fuel. Fuels like gasoline and jet fuel are mostly carbon and hydrogen, and burning them joins that carbon with oxygen from the air to make carbon dioxide. Because the oxygen adds weight, burning 1 kg of jet fuel makes about 3.16 kg of carbon dioxide. Engines also release smaller amounts of other greenhouse gases, like methane and nitrous oxide. Trains and electric cars often run on electricity made by burning fuel too.

Sunlight reaches us mostly as visible light, which passes through the air and warms the ground. The warm ground then gives that energy back off as infrared light, a longer wavelength we feel as heat. Nitrogen and oxygen, which make up most of the air, are each made of two identical atoms, and infrared passes right through them. Carbon dioxide, methane and a few other gases are built differently: their bonds bend and stretch in ways that absorb infrared, like a tuning fork that only rings at its own notes. They then send that energy back out in all directions, and part of it comes back down, which warms the planet. So these gases let sunlight in but hold some of the heat back.

See for yourself

Every purchase is on our public ledger, and every retirement is recorded on a public registry with its own serial number. Try it: search the ledger for dUa7, our founder's first trip, the San Francisco ↔ Newark flight at the top of the page. You'll see 1,001 kg across two tonnes, because that purchase also included a $5 chip-in to the community pool.