How much sleep do you owe?
Lose an hour here, ninety minutes there, and it doesn't disappear — it stacks into a debt your body keeps the books on. You stop noticing the tiredness long before your reaction time and your patience stop noticing it.
Log your week, see what you're carrying, and find the nap that actually helps.
Free · No sign-up · Two calculators, plain answers
Add up the last seven nights
Set the sleep you need, then drag each night to what you actually got. The gap is your running balance.
Drag the nights to see your balance.
Debt is the running gap between what you need and what you get. A single short night is mostly recoverable; it's the steady drip across a week that builds the balance the research warns about. Reaction-time comparisons are illustrative, drawn from sleep-restriction studies, not a clinical measure of you.
The debt hides better than the bill
Two things make sleep debt dangerous. The first is that the tiredness fades while the impairment doesn't — after a few short nights you stop feeling sleepy, but your reaction time, focus and mood keep sliding. You feel fine and perform worse, and you're the last to know. The second is that it doesn't clear the way people assume.
It accumulates
Need minus actual, every night, added up. Six hours against an eight-hour need is two hours down — by Friday that's a working day of sleep missing.
Weekends don't clear it
A long Saturday lie-in repays a slice, not the balance. After a long stretch of short nights it takes a week of full ones to get back to baseline, not two days.
The cost is invisible
The price shows up as slower reactions, a shorter fuse and foggier decisions, not as feeling obviously tired. That's what makes it easy to keep running.
So the move isn't a heroic 11-hour Sunday. It's nudging your nightly sleep up by fifteen or thirty minutes and holding it, night after night, until the balance comes back. A short nap can take the edge off today — but it buys alertness, it doesn't settle the account.
Nap right, or not at all
There are two good nap lengths and one to avoid. Pick what you're after, tell it when you'd lie down, and it'll give you the length and the latest you can start without wrecking tonight.
Skip the in-between nap. Around the 45-to-60-minute mark you're woken out of deep sleep, which is where grogginess comes from — shorter for a clean lift, or longer for a complete cycle, but not the muddle in the middle.
You can't nap your way out of it. You can stop adding to it.
Paying down a debt means getting full nights consistently — and the thing that usually blocks that is a night that won't start or won't hold. Moongreens is a melatonin-free night drink built to support your own wind-down, so the hours you mean to get are the hours you actually bank.
It leans on named clinical forms rather than a sedative hit, and on 5-HTP to support your own melatonin pathway rather than dosing the hormone itself. Made in the USA.
90 nights, money-back. Thirty nights isn't long enough to judge a recovery formula, so you get three months to feel the difference in how you wake up.
This calculator is for general guidance and isn't medical advice. Persistent tiredness or trouble sleeping can have causes worth checking with your doctor. These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.