Free, open-source, privacy-first AI usage tracking browser extension.
Effective date: September 17, 2026 · Last updated: September 17, 2026
These Terms of Use (“Terms”) govern your use of Treco, a free, open-source browser extension. Treco is a personal, non-commercial project developed and maintained by an individual developer based in Hungary — not a company, and not operated through any registered business entity. By installing or using Treco, you agree to these Terms. If you don’t agree, please don’t use the extension.
By installing, enabling, or otherwise using Treco, you confirm that you have read, understood, and agree to be bound by these Terms and by the Privacy Policy.
Treco is a free, open-source browser extension that observes your usage of supported AI websites, estimates the tokens, energy, CO2e and water associated with that usage, and presents that information back to you locally through a dashboard and popup. Treco runs entirely on your device. It is provided free of charge, with no paid tier, no advertising, no account system, and no server-side component of any kind.
You agree not to:
Treco’s source code is public and licensed under the MIT License — see Open Source & Licenses for the license text and third-party component attributions. The MIT License governs your rights to copy, modify, and redistribute the code itself, and these Terms separately govern your use of the extension as distributed to you (for example, through a browser’s extension store).
The “Treco” name and any associated logo are used to identify this project; no trademark registration is claimed at this time.
Treco observes your usage of third-party AI websites (for example, ChatGPT, Claude, Gemini, and others listed in Settings). Treco is not affiliated with, endorsed by, or operated by any of these providers. The developer does not control, and is not responsible for, the accuracy, availability, pricing, APIs, interfaces, or policies of any third-party AI provider. Changes those providers make to their websites may affect Treco’s ability to detect usage correctly.
The energy, CO2e and water figures shown by Treco are estimates for informational purposes only. They are not certified measurements, are not produced or verified by the AI providers themselves, and should not be treated as scientifically exact. They should not be relied upon for regulatory, compliance, financial, or scientific reporting purposes without independent verification. See Methodology and the Privacy Policy for how these figures are derived.
Treco is free, open-source software provided “as is” and “as available,” without warranties of any kind, express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, or non-infringement. There is no guarantee that Treco will operate uninterrupted, error-free, or compatible with every version of every supported AI website, or that its usage detection or estimates will always be accurate or complete. As a personal project, Treco is maintained on a best-effort, volunteer basis with no service-level commitment.
To the maximum extent permitted by applicable law, the developer of Treco will not be liable for any indirect, incidental, special, consequential, or punitive damages, or any loss of data, arising out of or related to your use of, or inability to use, Treco — including reliance on any environmental estimate it produces. Nothing in these Terms limits liability where it cannot be limited under applicable law.
Features of Treco may change, be added, or be removed at any time, as is typical of an actively developed open-source project. These Terms may also be revised from time to time; material changes will be reflected in the date above and, where appropriate, noted inside the extension. Continuing to use Treco after a revision takes effect means you accept the updated Terms.
You may stop using Treco at any time by disabling or uninstalling the extension. As a free, volunteer-maintained project, development or distribution of Treco could be paused or discontinued at any time (for example, if a browser’s extension store policies changed), with no guarantee of continued availability.
These Terms are governed by the laws of Hungary, without regard to its conflict-of-laws principles, unless a different jurisdiction is required by applicable consumer-protection law where you live.
See Contact for the current ways to reach the developer about these Terms — the project’s public GitHub repository is the primary channel.