Technical questions

  • Methodology

    Behind the Calculator lies a robust and detailed structure to calculate the carbon emissions and sequestration factors that ultimately give you a Carbon Report.

    We have outlined what methodology we follow and how Standards structure our work in the following documents and give an overview of how the calculations behind the Calculator work and references upon which they are based:

    Download Calculator Methodology v.3.2 (PDF, 3.06MB)

    Download References List (PDF, 139Kb)

    View References online

  • Updates to the Calculator

    We aim to update the Farm Carbon Calculator at least twice a year, sometimes more often. We always publish a list of what has changed since the previous update here in the Resources section.

    When any emissions or sequestration factors are updated in the Calculator, there will be a change in the carbon footprint of those particular items. Often these are relatively small changes, but in any case are due to new research or changes in scientific understanding of processes.

    For new reports all factors will be derived from the updated list of factors.

    This document provides an overview of what’s changed for the latest update of the Farm Carbon Calculator (April 2025)

    What’s Changed? April 2025 (PDF 2.91Mb)

  • How are crops emissions calculated?

    Emissions from crops are calculated based on how crop residues are managed and particularly from nitrogen released during decomposition, rather than on specific cultivation practices. The approach includes several residue management options for each crop, allowing for accurate emissions estimates based on what portion of above-ground residues are left in the field.

    When entering each crop grown, the more detailed information you provide about how you handle crop residues, the more accurate the resulting emissions footprint will be. If you don’t know details of how residues were managed then select the default option for each particular crop – which is a sensible average.

    For perennial crops (such as soft fruits, top fruits, biomass crops, and green manures), the calculator includes the crop’s renewal rate, or the frequency at which plants are replaced. This avoids overestimating residues and better represents the actual emissions in any given report period.

    The methodology follows the IPCC 2019 guidelines and incorporates emission factors specific to the UK, derived from the UK GHG Inventory and GHG protocol agricultural guidance. This ensures that calculations reflect both international standards and UK-specific data.

    Certain crops, like Christmas tree crops, are included for data tracking purposes only and do not have associated emissions calculations – where this is the case it is indicated within the calculator itself.

  • Confidence levels

    In the Report you will see a reference to Confidence Levels in the results. This refers to how much confidence we have in the actual figures produced by the Calculator for each item, on a range from 1 to 3, where:

    1 - lower confidence

    2- medium

    3 - high confidence

    This is because some items are inherently far more reliable and understood than others. For instance, diesel or electricity is high confidence - you know how much you've used and therefore the calculation for what the emissions are is quite mathematical.

    Conversely emissions from compost, or sequestration in hedgerows are difficult to be accurate with because they are biological and therefore there are a lot of variables.

    We therefore have the Confidence levels to give transparency. Please bear in mind however that every emissions/sequestration factor is backed up by firm science and we aim to provide the most accurate figures available.

  • What's included/excluded?

    The scope of the Calculator is scopes 1, 2 and 3 – meaning it is comprehensive and covers direct and indirect emissions. In IPCC Livestock calculations it covers Tiers 1 and 2.

    In line with other carbon calculators, we recognise that there is no one national or international standard that covers the exact requirements of a farm carbon report.

    PAS 2050 is widely used to calculate the GHG emissions from various products and services. Its methodology is used in the Calculator, however its scope falls short of what is required for a complete farm carbon footprint, in that it doesn’t include Scope 3 (indirect) emissions, nor carbon sequestration. Therefore our reports are only PAS 2050 compliant for the areas of which the Standard covers.

    We believe that this wider scope of the Calculator means the Farm Carbon Calculator is far more comprehensive and accurate for the user.

  • Renewables exported to grid

    In line with the GHG protocol agricultural guidance 2014 we no longer include "avoided emissions" for energy exported to the grid (electricity or biogas). The GHG protocol provides detailed guidance on how to properly monitor and report on grid-connected energy projects here.

  • The emissions source I want to add is not listed

    If you cannot find where to enter a particular emissions source on your farm into the calculator contact us to let us know. Describe what you were unable to add and our team will look to see whether it can be added and keep you informed where possible. We are always looking out for improvements we can make though research of new factors are prioritised based on demand, an estimation of the number of users it will serve, balanced with the impact it is estimated to have on the carbon footprint of reports.

Livestock

  • How much data should I enter into the livestock section?

    As a rule of thumb, the more accurate data you enter the more accurate your emissions values will be. We understand that data entry can be a slow process for large and complex farms, but we would encourage you to try to enter as much information as possible.

    There are certain parts of data entry that are mandatory as they underpin the calculations. These are animal type, number and the manure storage system used. You can enter as many manure storage set ups as is relevant to your system, but the calculator will require you to account for how your manure is managed for all 100% of your reporting period.  

    Other aspects of the calculation can be assumed using default values for the animal types. Each animal type has been assigned a default liveweight, for example dairy cows have a default weight of 685kg. You can override this figure to be your animals average liveweight, and we would recommend you do so as the liveweight is directly proportional to the quantity of manure produced (and the resultant manure emissions). Additionally each animal has been given a default enteric methane emissions rate, based on the UK GHG inventories reporting on the average diet and consumption rate of that animal type. For cattle and sheep this is a large part of the animals emissions, so you can override this to enter your exact dry matter intake of an average UK diet, or enter the exact diet your cattle and sheep are fed. Here too we would recommend entering this detail as using the UK average will likely overestimate your emissions. 

     

  • I have an old report and my livestock data looks different now?

    In May 2025 we expanded and improved our livestock calculation system so that the user could have more control over your footprint as livestock can be a major source of emissions on farm, and reliance on national averages could be over or underestimating your emissions. 

    In this update we have provided you with the capacity to migrate your livestock emissions into the new format, and also provided your previous data entry next to the new data entry locations so you can retain consistency. You can read more about how this update has changed the livestock emissions calculations system and how it may affect your reports here.

  • How does changing my cattle or sheep’s diet affect emissions?

    Diet digestibility and the quantity consumed are directly related to enteric emissions. More digestible feeds provide more energy for the animal, and leave less energy available for conversion into enteric methane. Each animal in the calculator has an assumed default enteric methane emitting rate, as set by the UKs GHG inventory and based on an assumed average diet and feed intake for that animal type. 

    For cattle and sheep you can override this by entering the daily dry matter intake so it reflects your animals consumption rates, and you can also select the diet the animals are consuming. In this way you can tailor the enteric emissions that will be produced to your system, rather than relying on a UK average for your animal type. Read more about enteric methane calculations and how to enter diet information here.

  • How are livestock emissions calculated?

    Total livestock emissions are made up of four components: enteric methane released by the animals, methane from manure, and nitrous oxide release from manure. Manure management, and ruminant animal diet can affect these components. 

    Enteric emissions are closely related to the quantity and quality of feed consumed. Cattle fed on a diet with a higher digestibility will have lower enteric emissions compared to consumption of the same quantity of feed of low digestibility, because there is more energy available for the animal in high digestibility feed. Read more about enteric emissions here.

    All animals produce manure, and manure quantity is determined by animal size, and the way this manure is stored and applied will impact emissions. Liquid slurry systems will have high methane emissions because the conditions are highly anaerobic, but you can control the N2O and NH3 emissions by covering the slurry and preventing volatilisation during storage. During application, broadcast slurry is liable to leach and run off in comparison to broadcast FYM, but you can mitigate against this through trail hose application or slurry injection. Read more about manure management systems here.

  • How do I record the average number of livestock I had on the farm last year?

    To arrive at your average figure, you can add together the total amount of livestock that was on the farm in each month, and then divide the total by 12. To keep things consistent, we suggest using the number that were on the farm on the first day of each month.

    For example, let’s say you’re working out batches (e.g. for chickens), and that you have 10,000 chickens, across 6 batches, for 30 days at a time (per batch). Your average would be 5,000.

    This is because there are 10k chickens on the farm for 6 months of the year, and none for the other 6 months. Adding 6 lots of 10k together (and 6 lots of 0) = 60k. Dividing by 12, you should arrive at 5,000.

    Alternatively, you can now also edit the reporting period you want to focus on in the livestock data entry. This will scale your emissions to the reporting period you present, meaning exact numbers of livestock can be entered for their exact reporting period.

  • Why does it matter how the average is recorded?

    Put simply, you can end up over or underestimating your emissions depending on how you’re recording the numbers - so it’s best to be as consistent as possible. If you take figures from your average from the start of one month and the middle of the next, your data (and results) are likely to be skewed.

  • How does weight and number of livestock affect carbon in the report?

    Both the weight and number of livestock do have an impact on emissions, but to different extents. The quantity of animals will generally impact the farm’s carbon footprint more than their average liveweight (we provide a default liveweight for each category of livestock in case you don’t have figures to hand).

    The weight of animals helps to estimate how much they will excrete and therefore estimate the greenhouse gases emitted from the management of manures. Entering “1” in the average head of livestock calculates emissions from enteric emissions and manure-related emissions assuming that one animal of the given weight was on the farm excreting every day of that year.

    This is why it is important to calculate an average for animals reared in batches or for animals that are only on the farm for part of the year (e.g. “bed and breakfast” animals, calves, replacements), otherwise emissions will be over-estimated. If you prefer to work with exact animal numbers, you can now use the report period to adjust emissions by the length of time the animals are being reported for. 

Further support

  • Can I have my report validated?

    Yes. Our team of expert advisors regularly validate reports as part of our own work and you can benefit too. Report validation can take place either in person or online and comes with a fee which may rise with the complexity of your business - but the more complex businesses will likely stand to benefit most from having their carbon footprints validated by us. We will assess for mistakes, irregularities, and provide feedback against benchmarks. Please note that this validation check cannot be relied upon for the purposes of participating in voluntary carbon markets.

    Read about our Calculator Services to see what is on offer or enquire about this service.

  • Do you offer consultancy services?

    Calculated your carbon footprint, but need some more help? We can assist your business in taking the next steps.

    We offer consultancy and training services to farmers and growers, organisations, and food chain businesses. This can include interpreting results, verifying data, creating a Carbon Action Plan, or doing soil analysis on your farm. Please see here for more information.

  • Do you offer advice? - for farmers and consultants

    There is advice on how to use the Calculator on our Resources page (plus a video here). If you are unable to find the answers you’re looking for, please contact us and we'll do our best to support you.

    To understand the meaning of your carbon report and plan your low carbon journey, please browse the Farm Carbon Toolkit and the various case studies on our website. If you’re a farmer with specific questions then we will do our best to answer them for you – please contact us. For anything more detailed, we offer consultancy services for farmers, advisors and companies.

  • Can I use the Calculator with my clients?

    Consultants and other users who are using the Calculator for profitable purposes are required to purchase an annual license from us and are not able to use the Calculator for free.

    Choose an appropriate package for your commercial use or alternatively contact us at ;[email protected].

    If consultants or other for-profit users are found to be using the Calculator for commercial purposes without license, FCT will at first attempt to engage with the company or individual to pursue relevant fees. If that route is not successful, and as a last resort, FCT will pursue legal action to recover costs and for breach of our Terms and Conditions.

Data & Reporting

  • Can I export my data?

    How do I download the carbon data from my Calculator report?
    Simply head to your report results and hover over the download button - you will see options here for PDF, CSV and JSON download. The PDF option will give you summary charts and tables as they are shown on the results page of the online Calculator while CSV provides key information about the report, as well as the emissions associated with each item you entered in the Calculator (as a breakdown) in a tabular format. JSON allows you to access all the data you have entered into the Calculator for that report as well as the emissions calculated for each item you entered.

    How do I download the data I have entered in the Calculator?
    Simply head to your report results and hover over the download button - you will see options here for JSON format. JSON allows you to access the data you put into the calculator (for example how many tonnes of red diesel you entered) as well as the emissions that were calculated for each item you entered.

    What is JSON format?
    Carbon reports are complicated, just like farming systems and businesses. Being able to share data and what it means between software platforms is also challenging, especially for data as complex as the reports you will produce using the Farm Carbon Calculator. To allow users to get the most from the process, we use JSON (which is a standard data format for representing bundles of different types of information) as a download to quickly provide all the data that you have inputted, as well as the results of the carbon calculation process. Other software platforms (such as farm management systems or reporting bodies) will be able to extract the data you need to share with them from these files.
     

  • How do I compare reports in the Calculator?

    Comparing Reports
    From the ‘Results’ section of any report, click the ‘Compare’ button. You’ll be taken to a selection screen where you can choose up to 5 reports to compare, and select either Timeline view or Compare view (explained below). Alternatively access the ‘Compare’ button from the sidebar on your dashboard (next to “My Reports”).

    What's the difference between 'Timeline' and 'Compare'?
    ‘Compare’ will allow you to view key metrics side by side for up to 5 reports - for example, seeing sequestration or carbon balance figures for several different farms. ‘Timeline’ plots the key data points from your reports over time, and allows you to track your progress toward net zero (in this case select reports that apply to the same farm or enterprise).

    Why can I only compare 5 reports?
    Currently we support comparison of 5 reports. Please do get in touch if you have a specific reporting need that involves comparison of more reports and we can discuss some of our professional licences.
     

  • Can I create a product footprint?

    You can use the Calculator to calculate either whole farm or product footprints. To do a product footprint (e.g. wheat), you need to spearate the processes used to produce the various food products from your farm. 

    This is an advanced process - read our guide (pdf) to help you through.

    For instance, you might have dairy cows, an arable operation, plus beef. First of all, work out what processes and inputs are used specifically for each of the three enterprises. Then work out what is common to all enterprises - e.g. buildings, machinery, office, woodland, hedges, etc. For these common elements, put everything in an Overheads report. Watch video on Overheads reports.

    Then create a product report (e.g. 'Wheat 2022') - add in the Overheads report, then all the inputs used for the wheat - e.g. diesel, electricity, fertiliser, distribution, etc. This will give you an accurate footprint for the wheat out of your farm.

    Repeat the process for the dairy and beef enterprises.

  • Farm types

    The Calculator can be used by farmers and growers with livestock, arable, horticulture etc. This includes farms on any scale, soil type or place in the UK.

    When setting up a new Carbon Report, you are asked to enter your farm details. This is so you can be clear what enterprises on the farm are being included, and we can assess data in the back-end of the system to generate (anonymous and aggregated) valuable benchmarking figures for sectors.

    There are various categories; tick any that are relevant to your business:

    Arable, Beef, Dairy, Fruit, Lowland grazing, Mixed (arable/livestock), Other, Pigs, Potatoes, Poultry - layers, Poultry - meat, Sheep, Upland grazing, Vegetables, Vineyards, Processing, Wineries, Non-agricultural business.

  • Is my data secure?

    As with anywhere where you are entering your farm business information we recommend you take basic steps to ensure a high level of security. Here at Farm Carbon Calculator we are also doing our part. Choose a strong password when registering your account and set up two-factor authentication from your dashboard for an extra layer of security. Our models allow us to reproduce and benchmark the data you enter but only in anonymous ways as part of a group.

    We employ regular internal and external testing to ensure our website, systems and servers are regarded as highly secure in line with industry best practice. Our team will never contact you to ask for your password so do not reveal this information to anyone. If you suspect unauthorised usage of your account or any other breaches of security you must let us know so that we can take action to protect your data and to help prevent further breaches. For details of how we handle your data and of our required response in the unlikely event of a data breach see our Privacy Policy and Terms & Conditions.

  • How do I delete my account?

    A member of our team can delete your account and all associated data with it. Contact us and use the email address you used when you signed up for your account. Your account will be deleted and you will receive a confirmation email. Before you do contact us make sure you download or export your reports if you wish to save these for a future date.

Using the Calculator

  • How long will it take to fill in?

    This depends on how complex your business is and how organised your records are! The longest part is collating your data in the first place, which could take anything from two or three hours to a whole day. However, once you know where to get the data needed, subsequent times are much quicker.

    Filling in data to the Calculator itself is straight forward once you have the necessary data, between around 30 mins and 2 hours.

  • Can I import my data?

    It is not possible to import your data into the Farm Carbon Calculator at present - though we are busy working on many different ways to import, or otherwise speed up your data entry and the process of creating your carbon report. Look out for our announcements and updates for when integrations with other popular software are ready to use.

    In the meantime remember that by copying a previous report you can speed up the process of data entry for next year - just make sure you edit each emission or delete any that no longer apply!

  • How do you calculate your carbon footprint?

    You need to enter data about your farm business, and through the Calculator we convert this in to a carbon footprint. We ask you for details about the following areas of your farm:

    • Fuels, electricity and business travel

    • Materials, machinery and buildings

    • Cropping and fertility

    • Livestock

    • Inputs (fertilisers and sprays)

    • Waste and recycling

    • Distribution (where applicable)

    • Processing (where appropriate e.g. packhouses, stores and wineries)

    • Carbon sequestration in soils and biomass

    Once you have the information, you fill in your data in our Carbon Calculator. To do this follow the instructions in the video on the Calculator home page, or use this guide.

  • How much does it cost?

    The Farm Carbon Calculator is free for all farmers and growers, and always will be. 

    For consultants or paid advisors using the calculator, we offer commercial licenses, bespoke versions and training. Visit our Calculator Services page and contact us to find out more.

  • What will my report show?

    It will show you the total carbon emissions and carbon offsets, expressed as tonnes of carbon dioxide equivalent (CO2e), percentage of total emissions/sequestration, and the carbon balance of your business.

    The results also show full detail of the emissions/offsets for every item you enter in the Calculator. Live results also appear as you enter in data, enabling you to compare the results of different items.

    Results are shown in varying levels of detail, highlight emissions hotspots, show Scope 1, 2 and 3 emissions, emissions of CO2e, nitrous oxide (N2O) and methane (CH4).

  • Where can I get more guidance for filling in the Calculator?

    As you go through the tool you will find help and information behind the green help symbols next to many of the items. For general guidance read through the guides available on our Resources page first, or watch the corresponding videos.

    You will find guides relating to:

    Quick Start Guide (start here)

    Gathering your data

    Overheads and product footprints (more advanced usage)

    Understanding soil carbon

    If you have a question which is not covered or just want to get in touch - Contact us and we will respond as soon as we can.

    You will also see on our resources page several Data Gathering Spreadsheets designed for different farm systems which offer a place to record the same information as required by the calculator offline – so you can prepare in advance to input this on the website, or use it as a guide to get thinking about what information you need.

  • What does 'Lock report' do?

    If you're looking through lists of reports, either to compare them or find them in your 'Dashboard', it can be useful to see at a glance which ones are complete or in use. The 'Lock report' button - which appears on the results page for each report - is used to let you mark that a report is finished.

    Once it is locked, you will no longer be able to edit it and it cannot be unlocked. You will still be able to make a copy of the locked report from your 'Dashboard' and edit that copy.

    Wherever you see a padlock icon next to a reports this indicates it is locked.