Hey Product Hunt! 👋

I'm the maker behind CaffeineTiming.

I wanted to answer a simple question: How much caffeine from my afternoon coffee might still be around at bedtime?

I found plenty of general advice about stopping coffee earlier, but I wanted something interactive where I could explore different drinks, times and bedtimes.

So I built CaffeineTiming.

Here's what it does:

☕ Estimate caffeine remaining at bedtime.

🕒 Explore an illustrative last-coffee planning time.

📊 Visualise caffeine decreasing over time.

➕ Combine multiple drinks in one calculation.

I also spent time simplifying the interface after realising that my original design asked too much of first-time visitors.

The calculator uses an educational half-life model. It doesn't diagnose sleep problems or promise that any particular cutoff guarantees good sleep.

It's free to use, with no account required.

I'd love feedback from the community:

Does the calculator make caffeine timing easier to understand? What would you improve?

Thanks for checking it out!