About Caffeine Half-Life Calculator

Caffeine Half-Life Calculator is a free online tool made to do one thing well: see how much caffeine is still in your system at bedtime, hour by hour.

We built it because the best web tools are the simple ones — no sign-up, no downloads, no clutter. Open the page, get your answer, get on with your day. It works on phones, tablets, and desktops, and it will always be free to use.

Who we are

This tool is built and maintained by Stoneman Enterprises LLC, a small independent studio that makes free, fast, single-purpose web tools. We publish a growing family of utilities — you can find links to our other tools in the footer of every page.

Contact

Questions, corrections, or feature ideas? Email us at stonemanenterprisesllc@gmail.com. We read everything.