Measure. Benchmark. Reduce.
BEST EMISSIONS CALCULATORS 2025:
THE SUCCESSOR TO CARBON CALCULATORS
Discover the best carbon emissions calculator for your needs:
Greenly
Greenly is a carbon accounting company that has supported 1,500+ companies measure, manage, and report on their carbon emissions. Through their starter plan (available for organisations with under 20 employees), you can easily get started. Greenly's full feature plans include dedicated support from a climate expert and account manager. The platform meets GHG Protocol standards, helping your organisation achieve relevant certifications and align with regulations.
Great for:
All industries
Scope 1,2,3 - spend based + activity based
Dashboards & detailed GHG emissions report
Final verification by a climate expert
Account management support
Reduction Plans included, SBTi support (higher plans only)
Worth checking:
Some features on higher plans only
Unravel Carbon
Unravel Carbon provides auditable GH emissions measurement aligned with the Greenhouse Gas Protocol and ISO 14064, certified by TÜV Rheinland, with full traceability of data and information flows for your external assurance. The platform allows you to generate carbon reports using real-time data, automated dynamic commentary, graphs, and insights. Export auditable reports containing relevant information that can be used as part of external disclosures.
Great for:
Scope 1,2,3 - spend based method
Dedicated customer support included in cost
Dashboards & detailed GHG emissions report
Data categories match that of accounting software
Worth checking:
Excludes extractive industries
Green Project Technologies
Green Project Technologies is the first carbon accounting platform that was purpose built for the private markets and supply chains. They have a client base of over 400 companies in the US, UK, EU, Australia, Africa, and South America have been coined the "QuickBooks of ESG Accounting.
Great for:
"Quickbooks" of carbon accounting
Carbon accounting: Scope 1,2,3 emissions
Dashboards and downloadable reports
Carbon savings, targets & tracking
Direct Data Integrations to 12k+ utility providers
Portfolio and Supply Chain Management
Microsoft Sustainability Manager
Microsoft Sustainability Manager automates data connections and calculations to help you record, report, and reduce your organization's emissions more efficiently. It is designed to help you better manage the constant flow of data from your operations and value chain. Microsoft Sustainability Manager helps you reach your sustainability goals while driving efficiencies, improving cost savings, and reducing energy consumption.
Great for:
Scope 1,2,3 - activity based
Support for streamlining data from vast number of sources
Seamless integration options for businesses using MS Azure
High reporting flexibility
Worth checking:
Starting cost of US$4,000 per month
Requires deep knowledge of sustainability
Asuene
Asuene is an enterprise climate cloud platform providing a one-stop solution to measure, report, and reduce carbon emissions. The platform allows users to manage Scope 1-3 emissions and Product Carbon Footprint (PCF) data. It is certified according to ISO14064-3 and utilises Al-OCR technology to streamline data collection, aiming to significantly reduce the man-hours required for CO2 measurement.
Great for:
Scope 1, 2, 3 and PCF management
 One-stop-shop for measurement, reporting, and reduction
 AI-OCR for efficient data scanning
 Certified according to ISO14064-3
 Consulting services available
Worth checking:
Market coverage:
Japan
APAC
USA
UK
Thailand
Taiwan / HK
HOW TO SELECT A CARBON CALCULATOR?
EVERYTHING YOU NEED TO KNOW
What do I need
to look for?
Firstly, when looking for a carbon calculator, make sure that emissions have relevant auditable emission factors for your company’s locations/ facilities and industries down to the product level.
What methodology
should it follow?
A calculator should be based on robust science and data for your relevant industry. Ensure that the platform's methodology is aligned to GHG protocol and supports your ability to make Science Based Targets.
What about
functionality?
Ideally, you want a platform that Instantly generates dashboards and reports for relevant metrics and Scopes. It should also be supported by climate experts to help check and verify the output. An easy onboarding process is a bonus.
Spend or Activity
based calculations?
Both, it’s best if the platform can make use of both methods to calculate your company’s footprint.
