Last updated: June 9, 2026
By downloading or using Tenon ("the App"), you agree to these Terms of Service. If you do not agree, do not use the App. You must be at least 13 years old to use the App.
Tenon is a set of woodworking calculators (board feet, cut-list and plywood-sheet optimization, fractions and feet-inches, miter and frame angles, board spacing, stair layout, and framing) and a tool for saving and organizing your projects. It is a planning aid for woodworkers and carpenters.
Tenon's calculators are built to be accurate and are tested against worked examples, but their results are guidance for planning and purchasing materials — not a guarantee of the exact amount or layout your project will need. Actual wood dimensions, saw kerf, blade width, grain, and cutting accuracy all affect real-world results. Building-code checks (such as stair rise and run) are informational only and must be verified against your local building code. Always measure and double-check before cutting. You are responsible for verifying quantities and dimensions for your own project, and for the safe operation of your tools and materials.
You retain full ownership of everything you create in the App, including saved projects, calculation results, material lists, and notes. This content is stored on your device and, if you use iCloud, in your own private iCloud account. Evelaina does not access or store your content.
You may use Tenon for personal and commercial woodworking purposes (including projects you sell). You agree not to:
The calculators are free. Tenon offers an optional auto-renewable subscription, "Tenon Pro", that unlocks unlimited saved projects and material-list export. Pro is offered as Monthly ($2.99) or Yearly ($19.99) — prices in USD; prices may vary by region and current pricing is displayed in the App.
The App's design, code, and calculator implementations are owned by Evelaina. Your saved projects and notes are yours. You may not copy, modify, or distribute the App itself without written permission.
The App is provided "as is" without warranties of any kind, express or implied. We do not guarantee that the App will be error-free, uninterrupted, or that any calculation will exactly match the needs of your specific project. Calculator results are provided for planning purposes.
To the maximum extent permitted by law, Evelaina shall not be liable for any indirect, incidental, special, or consequential damages arising from your use of the App, including but not limited to the cost of lumber or materials, wasted or insufficient materials resulting from reliance on a calculation, injury arising from the operation of tools, or loss of data due to device failure or App deletion.
We may update these Terms from time to time. Continued use of the App after changes constitutes acceptance of the updated Terms. The revised version will be posted at this URL with a new "Last updated" date.
These Terms are governed by the laws of the jurisdiction in which Evelaina operates, without regard to conflict-of-law principles.
If you have questions about these Terms, contact us at support@evelaina.com.
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