# 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. Reps places caffeine timing beside your sleep and readiness views, so the cutoff isn't an isolated stat sitting off to the side. The Readiness Score itself uses sleep, resting heart rate, and recent strain.

## 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?ppid=4ade4c5e-8372-4127-aa56-e0e280703826&pt=93716530&ct=caffeine-cutoff&mt=8)