Travel Tracking
Track Your Travel Carbon Footprint
Every trip, measured — across 9 transport modes
🚆 How you move is half the story
For many people, getting from A to B is one of the biggest single contributors to their personal carbon footprint — and the difference between modes is enormous. A short-haul flight can emit several times more per kilometre than a train covering the same route. The trouble is that most of us never see those numbers, so the choice between the car, the bus, and the rails feels abstract.
Decarbonr closes that gap by turning every journey you log into grams of CO₂e, so the impact of each trip becomes something you can actually compare — and reduce.
Nine ways to travel, one honest number
Real emission factors, not guesses
Log a journey across nine transport modes and Decarbonr applies genuine per-kilometre emission factors sourced from the European Environment Agency and the IPCC. If you enter two cities, the app auto-calculates the distance between them, so you don't need to know the mileage yourself.
Typical per-kilometre impact (illustrative):
- ✈️ Air travel sits at the high end of the range, often around 255 g CO₂e/km including radiative forcing.
- 🚗 A diesel car falls in the middle, roughly 192 g CO₂e/km for a single occupant.
- 🚌 Buses spread emissions across many passengers, near 105 g CO₂e/km.
- 🚆 Rail is among the lowest motorised options, around 41 g CO₂e/km.
- 🚲 Cycling and 🚶 walking are effectively zero.
Where it helps in real life
The daily commute
Log the same route by car one week and by train the next, and watch the daily total shift. Small, repeated trips add up faster than a single big journey — and they're the easiest to change.
The occasional flight
One long trip can dwarf months of careful choices. Seeing a flight land on your annual chart puts the rest of your footprint in perspective — and helps you plan.
The 2-tonne goal
Every logged trip feeds into your progress toward the sustainable target of about two tonnes of CO₂e per year — the level aligned with a 1.5°C world.
Travel is only one part of the picture
What makes travel tracking powerful in Decarbonr is that it doesn't sit in isolation. Your trips are combined with what you eat and more than a dozen other lifestyle categories — heating, electricity, water, waste, digital, and beyond — into a single daily number. Instead of juggling separate calculators, you get one honest figure that reflects your whole life and a colour-coded view of where your biggest opportunities are.
Because everything runs privately on your iPhone, your journeys and locations stay on your device. There is no account to create and no travel history uploaded to a server — the calculation happens on-device, and the data is yours.
And Decarbonr goes one step further than a tally: it shows what the world would look like if everyone travelled and lived like you, translating your annual footprint into a projected temperature pathway. It's a simple way to make an individual choice feel connected to the bigger picture — and to turn a moment of curiosity into a lasting habit.
Start measuring your trips
Download Decarbonr for iPhone and see the footprint of your next journey — and every choice around it.