Green Software

Research, tools, code, libraries, and training for building applications that emit less carbon into our atmosphere.

An awesome list created and managed by the Open Source Working Group in the Green Software Foundation.

Every entry is a link with a one-line summary: what it does, and the number behind it where one exists. Tooling comes first, grouped by what it measures — AI workloads, a cloud provider, source code, an operating system, a website. Then the organizations doing the work, the courses and books to learn from, and the research the whole field rests on.

Disclaimer

This list is created for informational purposes only and any links do not constitute an endorsement, recommendation, or favoring by the Green Software Foundation, its member organizations, or contributors to the list.

THESE MATERIALS ARE PROVIDED "AS IS." The parties expressly disclaim any warranties (express, implied, or otherwise), including implied warranties of merchantability, non-infringement, fitness for a particular purpose, or title, related to the materials. The entire risk of implementing or otherwise using the materials is assumed by the implementer and user. IN NO EVENT WILL THE PARTIES BE LIABLE TO ANY OTHER PARTY FOR LOST PROFITS OR ANY FORM OF INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY CHARACTER FROM ANY CAUSES OF ACTION OF ANY KIND WITH RESPECT TO THIS DELIVERABLE OR ITS GOVERNING AGREEMENT, WHETHER BASED ON BREACH OF CONTRACT, TORT (INCLUDING NEGLIGENCE), OR OTHERWISE, AND WHETHER OR NOT THE OTHER MEMBER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Topics: AI · AWS · Azure · Google Cloud · Multicloud · Source code · Carbon-aware scheduling · Energy monitoring · Linux · Mobile · Websites · Windows · Organizations · Courses · Research

Contents

• Tooling
• Organizations
• Courses
• Articles
• Books
• Research
• Related Lists
• About the Directory
• Contributing

Legend

Each entry ends with a kind badge: for software you can run, and a gray badge for , , , , , , , , for organizations, and for commercial products and vendor pages. Plain entries are articles. Entries marked unmaintained point at archived or abandoned projects kept for reference.

Tooling

AI — Carbon

• 1ClickImpact - A commercial API and platform for offsetting carbon emissions from AI workloads, with real-time tracking and Zapier integration for automated carbon accounting.
• AXIOMAX ESG Carbon Shield - An MIT-licensed SDK for Python, Node.js, and Bash that signs AI inference calls with ed25519 and SHA-256 hash chains to produce auditable carbon attestations for CSRD and SEC reporting; calibration coefficients and keys remain server-side, and the project advertises a pending USPTO patent.
• claude-carbon - An MIT-licensed Bash and SQLite tool that tracks the carbon footprint of Claude Code agent sessions, with a live CO2 estimate in the status line, per-model reports, shareable PNG report cards, and a published methodology.
• ebb-ai - An Apache-2.0 MCP server exposing nine tools that defer non-urgent LLM jobs to the cleanest grid hour within a deadline across 31 regions, logging per-task carbon receipts to SQLite. (source)
• Experiment Impact Tracker - A Python library that calculates the carbon cost of a machine learning job; unmaintained, archived October 2025.

AI — Energy

• carbontracker - Tracks and predicts the energy consumption and carbon footprint of training deep learning models, as described in Anthony et al. (2020).
• FedZero - A federated learning system for zero-carbon distributed AI training, successor to Lowcarb, which won the GSF CarbonHack 2022. (paper)
• ML.ENERGY Leaderboard - A public leaderboard from the ML.ENERGY Initiative showing time and energy consumption of generative AI models on GPU inference, covering LLMs, multimodal LLMs, and diffusion models.
• Zeus - An Apache-2.0 library for measuring and optimizing deep learning energy use across NVIDIA and AMD GPUs, Apple Silicon, Jetson, and CPU/DRAM, with power-limit and batch-size optimizers.

Cloud — AWS

• Customer Carbon Footprint Tool - A free AWS Billing console dashboard reporting Scope 1 and Scope 2 emissions in metric tons of CO2e by month, service, and geography, with a three-month data lag.
• Green Cost Explorer - A climate-related spend analysis for AWS from the Green Web Foundation; unmaintained, archived September 2023.

Cloud — Azure

• Azure Carbon Optimization - Resource-level emissions detail plus recommendations to reduce them, available from within the Azure Portal.
• Carbon Service REST API - Programmatic export of the data behind the Emissions Impact Dashboard and Azure Carbon Optimization.
• Well-Architected Framework for Sustainable Workloads - Microsoft's guidance on designing an Azure workload following Green Software Foundation best practices.

Cloud — Google

• Carbon Footprint - A free console dashboard reporting Scope 1, 2, and 3 emissions per project, service, region, and month, with dual location- and market-based Scope 2 accounting and BigQuery export.
• Cloud Jewels - An MIT-licensed set of energy-estimation coefficients and scripts converting GCP billing data into trailing 30-day kWh estimates for CPU, GPU, memory, storage, and network; unmaintained since 2020. (blog post)

Cloud — OVHcloud

• OVHcloud Carbon Calculator - A customer-facing calculator estimating monthly and yearly greenhouse gas emissions from manufacturing, use, and other indirect phases, covering over 300,000 bare metal servers outside the USA.

Cloud — Multicloud

• Carbonifer - A command-line tool to estimate and control the carbon emissions of cloud infrastructure before it is provisioned.
• Cloud Carbon Footprint - An open-source cloud energy and carbon emissions measurement tool spanning AWS, Azure, and GCP.
• Green Metrics Tool - A free open-source tool to measure the energy and CO2 consumption of a software architecture.
• kube-green - An open-source Kubernetes add-on that automatically shuts down selected resources when you do not need them.

Code-Based

• 1ClickImpact Sustainability API - A RESTful API for integrating environmental actions such as tree planting, carbon capture, and ocean cleanup into software and workflows.
• carbon-text - A syntax highlighter and snippets extension for carbon.txt files.
• CarbonLint - An MIT-licensed Tauri/Rust desktop app and npm CLI that tracks CPU, memory, disk, network, and GPU use, converts it to CO2 via regional grid intensity, and scores projects 0-100.
• CAST Highlight - Automated source code analysis that identifies green deficiencies and tracks improvement across an application portfolio.
• codecarbon.io - A Python library that tracks and helps reduce the CO2 emissions of your computing.
• Creedengo (formerly ecoCode) - SonarQube plugins for PHP, Python, Java, JavaScript, and more, providing static analyzers that highlight code structures with a negative ecological impact.
• energy-consumption-measuring-toolkit - Accenture's RAPL-based toolkit for measuring the energy consumption of Python applications.
• Green CodeQL - A GPL-3.0 collection of custom CodeQL queries flagging energy-related sustainability issues across six packs covering Java/Kotlin, Python, C/C++, JavaScript, C#, and GitHub Actions.
• JoularJX - Java software power monitoring at the source code level, in real time.
• Kernel Tuner - An auto-tuner capable of optimizing GPU code for energy efficiency.
• oaklean.io - A VS Code extension and test-framework integration that visualizes JavaScript and TypeScript energy consumption, identifies energy-intensive code sections, and suggests alternatives.
• Tracarbon - Tracks a device's energy consumption and calculates carbon emissions using your location.

General Purpose — Emissions

• Carbon AppInsights - An Azure Functions solution logging Electricity Maps emissions data for Azure regions into Azure Monitor for alerting triggers and automated actions.
• Carbon Aware Computing — Tools and Free Forecast Data - A NuGet package, PowerShell cmdlets, and a live SDK instance, plus an open carbon forecast for Europe in the Carbon Aware SDK's JSON format.
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