Compare the best carbon accounting software in Australia for 2025. See how Avarni and other platforms support the Australian Sustainability Reporting Standards (ASRS), the Greenhouse Gas (GHG) Protocol, and other key reporting frameworks.
As regulatory pressure increases and corporate climate targets become more ambitious, Australian businesses are adopting carbon accounting software to streamline emissions measurement, reporting, and reduction. But with so many platforms now available, ranging from fully automated Scope 3 systems to disclosure tools aimed at investors, choosing the right one can get complicated, fast.
This guide cuts through the noise. As of November 2025, we reviewed nine software platforms based in Australia or actively serving the Australian market, assessing how each handles emissions data, compliance with reporting standards (ASRS, GHG Protocol, ISSB), data collection methods, and real-world usability.
Why choose an Australian carbon accounting platform?
Choosing an Australian carbon accounting platform can give your business a practical edge. Local providers better understand the Australian Sustainability Reporting Standards (ASRS), evolving regulatory expectations, and the local operational context — from national emissions factors to procurement data. Local support also often means faster response times, better alignment with the Australian financial year, and deeper knowledge of Australian industries and supply chains.
If you need credible, audit-ready reporting for Australia, choosing a platform designed for the region can reduce compliance risk and simplify audits.
1. Avarni
Avarni is an award-winning Australian carbon accounting software company, founded in 2021 by former Atlassian and Macquarie Telecom Group staff Misha Cajic and Anuj Paudel, and backed by Main Sequence Ventures (co‑founded by CSIRO). Purpose-built for CFOs and finance teams in Australia implementing sustainability reporting, Avarni focuses on carbon accounting (particularly Scope 3 emissions) and supports organisations across Group 1–3 under ASRS reporting requirements.
Automation and compliance at scale
Avarni uses machine learning to automate emissions calculations for Scope 1-3, extract invoice and financial data, and apply emissions factors, reducing manual effort and errors. The platform is built to handle large datasets (including millions of rows), enforce consistent calculation rules, and generate audit-ready reports aligned with the Greenhouse Gas (GHG) Protocol, ASRS, and ISSB.
Scope 3 and supplier engagement
Avarni combines Scope 3 analysis with supplier engagement tools for collecting activity-based data directly from suppliers. Where supplier data is missing, it uses spend-based estimates and regional emissions factors to fill gaps and improve verifiability. The platform also provides scenario and forecasting tools to model emissions-reduction pathways against Australia's interim (2035) and net-zero (2050) targets.
Ongoing support
Every Avarni customer is paired with a dedicated implementation team to support onboarding, data validation, and compliance outcomes. Avarni also partners with advisory and technical firms such as BDO Australia, Jacobs, NTT Data, and Schneider Electric to provide extended ESG and implementation support.
2. Clear Carbon
Clear Carbon is an Australian platform that combines carbon accounting software with advisory services. It supports GHG Protocol alignment and helps businesses build emissions inventories that align with current reporting requirements. The platform may suit organisations that prefer a guided implementation approach, particularly where internal sustainability resources are limited.
3. Climate Zero
Climate Zero is designed for small to medium-sized businesses starting out with carbon accounting. It supports Scopes 1, 2, and 3 and includes features for forecasting and emissions planning. With a focus on accessibility and ease of use, the platform aims to make carbon reporting more manageable for teams without dedicated sustainability resources.
4. Greenbase
Greenbase has a long-standing presence in Australia’s carbon reporting space, particularly within sectors like mining, energy, and utilities. The platform supports detailed emissions calculation and compliance reporting, including NGER. It may be most relevant for organisations with complex regulatory obligations and established environmental reporting processes.
5. NetNada
NetNada offers a streamlined carbon accounting tool for small and medium-sized businesses. It supports both activity-based and spend-based methods and includes built-in climate action planning. The platform is designed for ease of use and quick implementation, with a focus on helping businesses get started with emissions measurement and reduction.
6. Pathzero
Pathzero now focuses on the financial sector, providing a disclosure and emissions risk platform for private equity firms and institutional investors. It enables users to assess emissions exposure across investment portfolios using data shared by portfolio companies. While no longer positioned as a general-purpose carbon accounting tool, it plays a growing role in financed emissions transparency and investor reporting.
7. Sumday
Sumday is a carbon accounting platform built for accountants, advisors, and finance teams supporting clients through emissions reporting. It integrates with financial workflows and helps facilitate the collection of Scope 3 data from suppliers. Sumday is particularly relevant for firms providing climate reporting services, rather than large enterprises looking to manage emissions directly within their own operations.
8. Trace
Trace offers a carbon accounting and offsetting platform tailored for SMEs, with a strong emphasis on climate storytelling and customer-facing dashboards. It provides baseline emissions estimates and supports progress reporting against broad frameworks. The platform is designed for businesses focused on brand-led climate action, rather than operational emissions management or supply chain analysis.
9. Workiva Carbon
Workiva Carbon is part of the broader Workiva reporting platform, combining carbon measurement with financial and ESG disclosures. While not developed specifically for the Australian market, it supports international frameworks such as the GHG Protocol and ISSB, and is used by organisations operating across multiple regions and jurisdictions.
