[ LEGAL ]
Licenses & Open Source Credits
Every line of code and artwork on this site is open and reusable — here is exactly what is licensed, and how.
Site code: MIT License
The source code of Age & Sleep Calculator is released under the MIT License. You are free to use, copy, modify, merge, publish, distribute, sublicense, and sell copies of the software, subject to the conditions below.
MIT License Copyright (c) 2026 Age & Sleep Calculator Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
If you build something with this code, we would love to hear about it — but the license does not require it.
Icons and artwork
All icons and artwork on this site, including the logo mark, menu, theme, and calculator icons, are original custom inline SVG. They are publicly reusable: you may copy, adapt, and use them in your own projects without attribution and without asking for permission.
Fonts
This site uses a system font stack only. No third-party fonts are loaded, so typography adapts to each visitor's operating system, keeps pages fast, and never sends requests to font providers.
JavaScript libraries
The site includes no third-party JavaScript libraries. All scripting is written in-house and kept deliberately small, which keeps pages fast and reduces the surface area for tracking or breakage.
PWA and service worker
The progressive web app behavior, including the manifest and the service worker that enables offline use, is implemented according to open web standards from the W3C and WHATWG.
Trademarks
Trademarks belong to their respective owners. This site does not use any trademarked names, logos, or branding. If you believe any content here conflicts with a trademark, please contact us.