Terms of Service

Last updated: 14 September 2026

Equation.io is a free graphing calculator and MCP service for exploring mathematics. Check results before relying on them, keep copies of important work, and share graph links only when you intend to share their contents.

About these terms

These terms govern use of equation.io and its MCP endpoint, operated by Anthony Foster in Australia. By using the service, you agree to these terms. If you do not agree, please stop using it. Questions can be sent to support@equation.io.

Using the service

No Equation.io account or API key is required. You may use the calculator and MCP tools for lawful personal, educational, research, and commercial purposes. You are responsible for having permission to use the content you enter and for your use of the results.

Do not use the service to break the law, infringe others' rights, attempt unauthorized access, introduce malicious code, evade reasonable access restrictions, or deliberately overload or disrupt the service. Automated MCP use is welcome subject to reasonable operational limits.

Your content and graph links

You retain any rights you have in your equations, data, and other content. You give us permission to process and return that content only as needed to provide the service, including generating graph links and previews.

A graph URL contains the graph's equations and related text. Anyone with the URL can read, copy, modify, or share them. Creating a new link does not overwrite or revoke an old one. We do not provide private graph accounts or a service for deleting links from recipients' browsers, messages, or other systems.

Imported CSV files are stored locally in your browser where supported. They are not backed up by Equation.io, and the graph URL does not include their file bytes. Keep your own copies of files and work you need.

Accuracy and limitations

Graphs, symbolic computations, numerical results, and input validation can contain errors or approximations. Features can behave differently across devices and browsers. Validation does not prove mathematical correctness, and a finite plot can miss discontinuities, roots, or other features.

MCP preview images are simplified static renderings. They can omit features that the interactive calculator supports, and animations are shown at a single time. Review the returned validation messages and preview limitations.

Independently verify results before using them in consequential decisions, including engineering, medical, financial, or other safety-critical work. Equation.io is not a substitute for qualified professional advice.

Other services and privacy

Use through ChatGPT, Claude, MCP gateways, GitHub, or other third-party services is also subject to those services' terms and policies. They may charge fees or apply their own limits. We do not control their availability, data handling, or the accuracy of AI-generated equations and explanations.

Our Privacy Policy explains how the calculator, MCP server, browser storage, and hosting infrastructure handle information.

Availability and changes

We aim to keep the service useful and available, but do not promise uninterrupted operation, a particular level of support, or permanent availability of every feature. We may make changes, apply rate limits, or temporarily restrict access to address maintenance, security, abuse, or legal requirements. Where reasonably practicable, we will give notice of material changes that affect normal use.

Consumer rights and responsibility

Nothing in these terms excludes, restricts, or modifies any consumer guarantee, remedy, or other right that cannot lawfully be excluded, including rights under the Australian Consumer Law.

Subject to those rights, the service is provided as available, without additional promises that it will be error-free, meet every requirement, or preserve your work. Each party remains responsible for its conduct as required by applicable law.

Open-source software

The current Equation.io source code is available under the MIT License. These service terms do not limit rights granted by that license. Separately licensed historical versions remain subject to their own licenses.

Updates and contact

We may revise these terms for changes to the service or legal requirements. We will publish the revised terms here with an updated date and highlight material changes on the site. Changes apply prospectively; if you do not accept revised terms, stop using the service.

For support, use GitHub issues or email support@equation.io. GitHub issues are public, so send private matters by email.