What is a business carbon footprint calculator?

A carbon footprint calculator is a tool that can help you and your team to measure the greenhouse gas emissions that you generate as a business. These calculators come in different shapes, ranging from simple, do-it-yourself style Excels, to guided software platforms that are more accurate and do the heavy lifting for you. 

What is the right Carbon Footprint Calculator for your business?

The right carbon calculator for your business depends on what you’re looking to achieve. Sometimes, a simple calculator is a great starting point. That’s why we’ve created a free Excel-based calculator, and this article to help you use it.

This tool might be a great fit for you if:

• You’re happy with a simplified, initial look at your footprint - not fussed on detail / accuracy.
• You don’t need it to be complete / comprehensive.
• You have the time to roll your sleeves up and get to grips with how carbon accounting works.
• You don’t need to report a third-party verified footprint.

If you’re looking to get an accurate, comprehensive view of your emissions, and you’d like support from an expert to make the process quick and straightforward, without breaking the bank, check out Seedling’s easy-to-use carbon accounting software.

Why should your business calculate a carbon footprint?

There are loads of reasons your company should measure and aim to reduce its greenhouse gas (GHG) emissions, beyond the obvious case for environmental stewardship and tackling climate change: 

• Spot opportunities for cost savings by using resources more efficiently. 
• Make sure you comply with emissions reporting regulations (e.g. SECR).
• Attract and retain top talent by demonstrating that you’re a considerate employer.
• Meet the expectations of your clients by providing emissions data, and committing to reduce your footprint, increasingly a criteria in RFPs.

How does our free carbon footprint calculator work?

Our free business carbon footprint calculator is designed to cover Scope 1 (direct emissions), Scope 2 (indirect emissions from purchased electricity), and some of the most common Scope 3 categories (take a look at the notes section of the calculator to see exactly what’s included and excluded). For businesses that are relatively simple from an operational perspective (e.g. professional service firms), the calculator will capture the majority of your main emissions sources, with the exception of the things you buy - (category 3.1 purchased goods and services). Unlike calculators that rely purely on spend-based metrics, Seedling’s free carbon calculator uses activity-based data for a more accurate footprint.

How does measuring a carbon footprint actually work in practice?

Put simply, measuring your emissions involves multiplying your business’s activity data or spend data (things like kWh of electricity consumed) by the relevant ‘emissions factor’ (sometimes called a ‘conversion factor’). The role of emissions factors is to convert your business’s activity into the GHG output of that activity. 

Databases of emissions factors are calculated and published by a range of organisations, including governments, academics and non-profits. In the UK, DEFRA publishes emissions factors for businesses to use in reporting their GHG emissions each year. 

If you take a look at the diagram below, you’ll see measuring emissions from electricity consumption as an example. Your business’s activity data (in this instance the amount of electricity consumed in kWh per your bills) is multiplied by the relevant emissions factor as published by DEFRA (tCO2e per kWh of electricity consumed in the UK).

What will my emissions output look like? What is tCO2e?

Your emissions impact will be expressed in a unit called 'carbon dioxide equivalent' (CO2e). There are many different types of greenhouse gases, and each has a different warming impact (you can think of this as potency). CO2e simplifies the way we talk about carbon footprints by expressing the impact of all GHGs in terms of the equivalent impact of carbon dioxide (CO2). This means we can talk about and compare one number, rather than all greenhouse gases separately.

Step-by-Step Guide: How to Calculate Your Carbon Footprint in Excel

So, how do I use Seedling’s free business carbon calculator? For those that want to roll their sleeves up and have a go at calculating a simple footprint, we created this basic carbon footprint calculator in Excel. Below is a step-by-step guide on how you can use it.

Before we begin, a quick reminder: this calculator is not comprehensive (the Scope 3 categories excluded are listed clearly, so you can be sure what’s included and what isn’t). The reason for this is that, unlike the included categories which apply to almost any business, the remainder of Scope 3 becomes complex and nuanced depending on the sector you operate in. 

If you’re keen to get stuck in and measure a full scope footprint yourself, you’ll need to decide which of the excluded Scope 3 categories apply to your business, and apply the same methodology. Collect the best data (activity or spend based) that your business holds to reflect that activity. Next, take a look at the DEFRA emissions factors, as well as emissions databases specific to your sector, and use those conversion factors to create a GHG output. 

At Seedling, we handle the heavy lifting and complexity for you, helping you and your team to measure a footprint that’s comprehensive and maximally accurate. If you’d like a hand, we’d love to chat.

So, let’s get stuck in!

Step 1: Define your scope

First thing’s first, you’ll need to define the ‘organisational boundary’ of the footprint you’re measuring (i.e. the specific entity / entities you’re going to include). 

If your business has subsidiaries, under the GHG Protocol you can decide whether to account for these emissions based on the equity share you hold in the subsidiary (e.g. 50% equity share = 50% of emissions attributed to the parent company), or simply make a decision to include 100% of subsidiary emissions, or none at all, based on whether or not you control the operations of that entity. The aim: include all emissions that your company has the power to influence.

You also need to choose the annual period over which you’re measuring your emissions. It’s best practice to align with your FY, so that planning around emissions measurement aligns with broader business forecasting.

Step 2: Identify your emissions sources

If you haven’t already, it’s now time to get the free calculator open in front of you. As you’ll see, cells B3-10 list sources of emissions. Step 1 is to decide which of these categories apply to your business. For instance, if your team works entirely from home, commuting emissions won’t apply.

Step 3: Collect your emissions data

You’ll now need to fill in cells D3-10 with your activity data. Column C lists the exact datapoint you’ll need for each category. Here’s a quick summary of where to look for the data you’ll need.

• Utilities data: energy consumption, measured in kWh, should be listed on your bills for both electricity and gas. You may need to check with your landlord to get your hands on this information. If your bills aren’t available, it’s possible to estimate your emissions based on the floorspace and type of facility you occupy, so chat to the Seedling team.
• Company vehicles: some companies operate a software-based tracking system to monitor mileage of fleet. If this option isn’t available, you’ll want to take a look at your fuel receipt totals and convert that number into mileage, using your rate for the year.
• Employee commuting & WFH: the easiest way to capture this information is to survey your team to understand their commute (how far, how often, transport mode), and working patterns (on average, when are they in the office vs. at home. vs elsewhere). Shameless plug alert: Seedling’s ready-made employee survey makes this process easy and engaging, and the data is automatically populated to your dashboard (no analysis needed). Send us a message if you'd like to learn more.
• Business travel: your main options here are travel booking portals (such as Trainline for business, portals with a travel agent, or airline apps), or travel expenses data. If your expenses data is poor, it may be a better option to ask your team about their travel over the year in your employee survey.

Once you’ve gone through this process for the first time, it’s a good idea to think about standardising your data collection to streamline data gathering in the future. You could consider tweaking the input criteria on expenses forms to gather the data you need, adopting travel portals, or sharing your employee survey on a monthly basis to improve accuracy of recall.

Step 4: Choose and apply your emissions factors

In columns E & F, we’ve included emissions factors as published by DEFRA, and the corresponding description. Be sure to read the detail in column F and make sure it matches the activity data you’ve entered in column D.

These conversion factors are for 2024. To calculate prior years, you’ll need to update column F with DEFRA’s factors for that year.

Step 5: Add missing data

You might be keen to expand the assessment to include additional categories (for instance, to record long haul flights ). Now you understand the methodology, all that’s left to do is to repeat it, adding a new row with the relevant business data and matching conversion factor from DEFRA’s database.

Step 6: Interpreting your results

Once your data is complete, the calculator will produce a quick visual categorising your emissions by scope. You may want to produce further charts to deep dive into hotspots for your business (business travel by mode of transport, for instance).

Next, you’ll want to understand your emissions in context. Here’s a couple of quick tips on further research you can do: 

1. Compare against industry benchmarks: Identify average emissions data for your industry. Reports from industry associations, or sustainability benchmarks like CDP (Carbon Disclosure Project) often provide emissions data segmented by sector.
2. Use intensity metrics: Normalise your emissions by using intensity metrics, such as emissions per employee, emissions per unit of revenue, or tCO2e per unit shipped if you’re a product business. Intensity metrics will help you compare your footprint with businesses of different sizes. They’re also a great KPI for target setting, helping you to account for your growth (especially important for scale-ups and start-ups).

And that’s a wrap!

Congratulations on taking the first step to understanding and reducing your business emissions. We hope this guide has been helpful.

Looking to measure a comprehensive and accurate footprint, and save time?

Seedling helps 100+ teams get expert support with measuring a maximally accurate, full scope footprint, without breaking the bank. We make the process easy, save you time, and support beyond measurement, with reduction advice, decarbonisation modelling, and target setting (e.g. Net Zero). 

We’d love to chat!

Additional Resources

For more information on emission reduction strategies, carbon accounting, and how your business can move towards Net Zero, explore our other guides and toolkits:

Seedling Climate School - the go-to resource for carbon literacy and emissions reduction.

Seedling Says - check out the latest insights.

Seedling Starter - software to get you started with a simple footprint. Join the waitlist.