Calculate your business emissions

Our free-to-use calculators help measure your business emissions.

Why calculate?

The Global Role of SMEs

Small and medium sized companies (SMEs) make up 90% of global business and are the foundation of the world’s value chains.

Collective Impact on the Climate

Though the individual footprint of an SME might be small, together they contribute a sizable amount to the global carbon footprint. Many SMEs want to act but may not know where to start.

Why Measurement Matters

Measuring and understanding your emissions is a great first step to help your business start taking meaningful action.

Our calculators

Use our calculators to measure your emissions successfully.

To help you get started, see our action guide for advice on how to approach calculating your carbon emissions.

Small Business Carbon Calculator

A simple, accessible calculator, for small businesses starting their carbon measurement journey. Designed to help make sense of carbon measurement and identify emissions hotspots.

Starting point for small businesses with one site
Available in multiple languages
Scope 1, 2 & 3

Advanced Business Carbon Calculator

A comprehensive, transparent and auditable calculator, ideal for medium and large businesses, with the flexibility to incorporate data from multiple sites. This provides enhanced carbon measurement to accelerate progress towards Net Zero.

Best for multi-site businesses
Auditable spreadsheet tool
Scope 1, 2 & 3

Compare tools

Compare calculators and find the one that suits best for you.

Best For

Format

Scope

Business Size

Cost

Information required

Language

Small Business Carbon Calculator

Best For

One-site businesses

Format

Simple online tool

Scope

1, 2 & 3

Business Size

1-50

Cost

Free

Information required

Basic

Language

English, French, German, Italian, Portuguese (Portugal), Portuguese (Brazil), Spanish, Swedish, Arabic

Advanced Business Carbon Calculator

Best For

Multi-site businesses

Format

Auditable Spreadsheet

Scope

1, 2 & 3

Business Size

Any

Cost

Free

Information required

Intermediate

Language

English

Advanced Business Carbon Calculator was a revelation, it held my hand through the process with simple, clear and concise instructions. Now I have a basis to start plugging away at reducing our GHG impact.

Charlie Westhead

Owner of Neal's Yard Creamery

Using the Advanced Business Carbon Calculator has simplified the process of measuring our carbon footprint and has helped us to expedite our approach to decarbonisation.

Geraldine Hogben

Operations Director at Fundamental Media

Have questions?

To help you get started, see our action guide for advice on how to approach calculating your carbon emissions.
If you have any questions about our carbon measurement offering then please visit our FAQ. If your question is not covered by the FAQ or if you would like to give feedback on any of the carbon calculators then please contact us via our form and select the topic “Tools and Resources”.

Visit FAQ Guide for measuring your emissions

What’s new in the latest version of the Small Business Carbon Calculator?

Released in September 2026, version 2.1 of the Small Business Carbon Calculator includes the following updates:

Now in eight more languages: The calculator is now available in German, Italian, Spanish, French, Portuguese (Portugal), Portuguese (Brazilian), Swedish and Arabic.
Coverage for 179 countries: We’ve added electricity emission factors for countries across the Global South, so coverage has grown from 50 countries to 179. SMEs in these countries now get more accurate results based on where they operate.
Finalise your report: Once you’ve calculated your emissions, you can finalise the report and use it in your own reporting. Finalised reports also let you track your progress year on year.
Full Scope 1 and 2 coverage: A new question on purchased heating means the calculator now captures all the data you need for Scope 1 and 2 emissions.

Small Business Carbon Calculator release history

Version 2.1
Released 30 September 2026

Update to 2026-released emission factors
Added electricity emission factors for countries across the Global South
Coverage extended to cover 179 countries
Updated fugitive gas methodology for all countries
Updated home working and co-working to 2026 values and to cover all countries
Support for nine languages (English, German, Italian, Spanish, French, Portuguese (Portugal), Portuguese (Brazilian), Swedish and Arabic)
Full Scope 1 and 2 coverage
Ability to finalise your report, so that you can track progress year-on-year

Version 2.0
Released 26 September 2025

Update to 2025-released emission factors
Inclusion of fugitive emission estimates in Scope 1
Inclusion of Scope 3.5 (Waste Generated in Operations/Water Generated in Operations)
Inclusion of Scope 3.4 (Upstream Transportation and Distribution) and 3.9 (Downstream Transportation and Distribution)
Inclusion of co-working and serviced offices in 3.8 (Upstream Leased Assets)
Inclusion of self-generated and certified renewable electricity
Provision of Market-based and Location-based Scope 2 reporting
Addition of mileage-based estimates for Scopes 3.6 and 3.7
Addition of electric vehicles to Scopes 3.6 and 3.7 (when charged away from owned facility)
Improved reporting including intensity metrics
VSME reporting aid for EU SMEs

Version 1.0
Released 1 May 2025

Migration from Normative/Google calculator
Updated interface and direct connection to SME Climate Hub logins
All data now stored by SME Climate Hub
Methodology improvements to use activity data rather than average or spend-based for Scopes 1, 2, 3.3 and 3.6 (Business Travel) and 3.7 (Employee Commuting & remote working)
Addition of home-working emissions to 3.7
Improved reporting, including Scope break-down and PDF download