# Caffeine cutoff — know when to stop

Most trackers show a running caffeine total for the day. Reps goes further: it tracks how much caffeine is still active in your system right now and tells you the latest time you can have more without it working against tonight's sleep.

## How the cutoff works

Reps models how caffeine clears from your system over time and combines that with your own sleep patterns to calculate a personal cutoff — the point in the day after which more caffeine is likely to cost you sleep tonight. It's tuned to your body's own pace, not a fixed rule like "no coffee after 2pm" that ignores how differently people actually process caffeine.

## Why it's tied to sleep, not just a total

A daily caffeine total tells you how much you drank. It doesn't tell you whether that afternoon coffee is still active at 11pm and quietly eating into your sleep — and therefore into tomorrow's Readiness Score. Reps connects the two: caffeine timing feeds into the same sleep and readiness picture the rest of the app uses, so the cutoff isn't an isolated stat sitting off to the side.

## What you see

Reps shows how much caffeine is currently active in your system and a real cutoff time for the day, updated as you log drinks — not just a static daily limit set once and forgotten.

## No extra hardware

Caffeine and sleep tracking both run off data Reps already has from your logging and your Apple Watch — no separate sensor or subscription required.

## What it isn't

This is a training and sleep-quality tool, not a medical dosing guide. It doesn't diagnose caffeine sensitivity or make health claims about caffeine intake — it's a practical cutoff based on your own logged patterns.

[Download Reps on the App Store](https://apps.apple.com/app/id6746460451)