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
Simple online tool
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

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

Advanced Business Carbon Calculator

Best For

Multi-site businesses

Format

Auditable Spreadsheet

Scope

1, 2 & 3

Business Size

Any

Cost

Free

Information required

Intermediate

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

Notice for users of the Emitwise Scope 3 Specific Calculator

The Emitwise Scope 3 Specific Calculator was permanently closed on 16 July 2025.

All data has been deleted and the portal is no longer accessible.
You can continue your sustainability journey with our other free calculators listed on this page.

If you need additional support or have any questions, feel free to contact us via the inbox so we can assist you on a case-by-case basis.