Do you want to lose a few tons?
Reading time : 5 minutes
|Published on : 19/02/2025

Contents
The story behind Nos Gestes Climat
This slightly provocative invitation to lose a few tons is nothing new, it was already the slogan of Coach Carbone, launched in 2010 by ADEME and the FNH (Fondation pour la Nature et l’Homme), founded by Nicolas Hulot. Nearly a decade later, the challenge of taking action remains just as relevant! Climate change is everywhere and awareness has grown significantly, more and more citizens are eager to act for the ecological transition.
Although Coach Carbone has since ceased its activities, other carbon footprint calculators have risen to the task.. But it’s not always easy to know which one to trust. This is why ADEME, through Datagir, and the Bilan Carbone Association (ABC) decided to develop a easy to use and open tool. More importantly, a tool that is not just about measuring our weight in CO2e. We also need guidance on where to start our "carbon diet" and what actions we can take in our daily lives.
So let’s look back at the origins of our simulator, a project shaped by the hard work of many contributors whom we want to acknowledge and sincerely thank!
"Coach Carbone": An ADEME and FNH initiative from 2010
Launched on October 7, 2010, Coach Carbone helped users measure their CO2e emissions through a structured evaluation covering four key areas: housing, transport, food and equipment. It can still be found in the depths of the internet, for example, in this Actu Environnement article or this piece from Le Monde. If you’re curious, internet archives provide a glimpse of what it looked like.
What has changed since then? At the time, France aimed for a Factor 4 decrease (reducing emissions by four compared to 1990 levels by 2050). Now, ten years later, legislation mentions Factor 6 and beyond (see details here), as greenhouse gas emissions have continued to rise, reducing our available carbon budget.
The message is still relevant today, isn’t it? And the campaign from back then is just as true. Here are some visuals from 10 years ago, content-wise they haven’t aged a bit:
In 2010, "MicMac" was also created
"Mon Impact Carbone, Mes Actions Concrètes" ("My Carbon Impact, My Meaningful Actions"), an accurate summary of the goals pursued by the TaCa association when it developed its first carbon calculator spreadsheet in early 2010 based on ADEME's Personal Carbon Footprint tool. The name "MicMac" was also chosen because this somewhat old-fashioned term reflected the confusion in media and public perception regarding greenhouse gases at the time.
Even though climate awareness has significantly grown over the past decade, confusion still persists, and most people remain unfamiliar with the true scale of emissions.
With the same goals in mind, young volunteers from the Avenir Climatique association partnered with TaCa in 2014 to develop a more comprehensive MicMac spreadsheet. By 2017, the MicMac tool was available online on Avenir Climatique’s website, and in 2018, it was chosen by the On Est Prêt collective as their preferred personal carbon impact assessment tool.
2020: A new easy to use and open calculator
While Coach Carbone ceased its activity, MicMac is still in use today. However, many other calculators now exist, as some are specialized in specific sectors, some are designed for a simpler user experience, and others focus on carbon offsetting. Given this landscape, the Association Bilan Carbone (ABC) conducted a review and evaluation of available online calculators. Their detailed comparison showed that MicMac was an excellent foundation to raise awareness about the greenhouse gas emissions of our daily activities.
Being both comprehensive and open, the teams at ABC and Datagir decided to build upon this tool to develop a calculator that is just as effective but designed for a more user-friendly experience, making it easy to integrate into different platforms, such as Mon Impact Transport. More importantly, they aimed to create a shared resource that would spark an engaged and growing community by:
- Pooling efforts in CO2e accounting, compiling emission factors into reusable libraries for developers and product managers, documenting data, challenging existing calculations, collecting feedback, and encouraging contributions.
- Bridging the gap between carbon experts and users so as to better understand user needs and challenges while highlighting the complexity of Life Cycle Analyses (LCA) and current calculation limitations.
- Opening and sharing data and calculations providing transparency on methodologies, balancing simplicity and precision, and calculation assumptions.
- Encouraging the reuse of this data while adding it into familiar tools and services to enhance awareness and climate action.
- Making carbon accounting as intuitive as tracking money so that understanding and managing one’s carbon footprint becomes second nature.
Let’s remember: the first goal of the calculator is to provide clear and simple estimates quickly, without asking an overwhelming number of questions, especially when we need to reduce emissions by six or more.
Among the many user suggestions received so far, some have highlighted the need to specify whether their electricity provider is green (issue link) or the type of fuel used (issue link). No calculator is perfect, they all aim to make reality more accessible and more understandable. While a gram-precise carbon footprint may sound appealing, it is neither realistic nor useful given the urgency of reducing our greenhouse gas emissions. Understanding the big picture and comparing emission categories is already enough to drive meaningful changes in our lives.
In 10 years, when our average carbon footprint drops to 3.5 tons of CO₂e, we can focus on the details of getting below 2 tons and analyzing the impact of individual products.
A footprint assessment is good but actionable solutions are better
Let’s be honest: even for those who consider themselves environmentally conscious, the final carbon footprint result can sometimes be surprising or even discouraging. The gap between our aspirations and reality can be quite shocking. Yes, the path to carbon neutrality is a steep one, requiring both individual and collective efforts to transform our societies. But beyond awareness, the key is to guide citizens toward progressive improvements based on their current situation.
That’s why our calculator doesn’t just assess your impact, it also suggests purposeful actions adapted to each individual. Even better, it shows the impact of each action based on your personal situation, helping you track how much CO2e you can cut, whether by a few kilos or even a full ton.
While the goal is to steer users toward high-impact actions, we recognize that most changes take time. It’s important not to take on too much at once, but rather to identify achievable steps and maintain them over time.
The key is to gradually understand the impact of different actions, whether structural (like home insulation), behavioral (like driving more efficiently), or habit-based (like reducing meat consumption). Each user can then choose the steps that are immediately actionable and plan for future improvements.
Everyone must decide where they can and want to start based on their situation. Common advice, such as turning off lights, does have an impact but far less than reducing heating consumption or avoiding solo car trips. That’s why we quantify each action to help users understand the scale of impact involved.
So, is carbon offsetting the final solution?
Many carbon calculators today focus on offsetting often by funding tree-planting projects. However, these solutions do not guarantee that carbon remains stored for the decades or centuries required.
- Time issue: trees take decades to absorb CO2 while a plane releases emissions instantly.
- Spatial issue: those who offset their emissions are often not the ones suffering the consequences of climate change.
Offsetting isn’t just about preserving existing forests. To truly offset emissions, we need to expand current forests by planting additional trees a process known as "additional offsetting." But remember: a forest isn’t just a collection of trees it’s a complex ecosystem that takes centuries to develop.
The real priority? The ARC rule:
- A for Avoid,
- R for Reduce,
- C for Compensate (as a last resort).
Compensation should only come after emissions have been reduced as much as possible.
So, are you ready to lose a few tons of CO₂? Start now with the Nos Gestes Climat calculator!

Julie,
For the past ten years Julie has been committed to the transition of our society. She joined the Nos Gestes Climat team in 2023 as a carbon specialist and is responsible for the clarity of the calculator and published content.