Set a Bedtime for School Wake-Ups

Work back from the school alarm to a consistent, cycle-friendly bedtime.

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Wake-up time

Go to bed at

9:45 PM

9 hrs

6 cycles · ideal

Go to bed at

11:15 PM

7.5 hrs

5 cycles · ideal

Go to bed at

12:45 AM

6 hrs

4 cycles

Go to bed at

2:15 AM

4.5 hrs

3 cycles

💡 Sleep happens in ~90-minute cycles. Waking at the end of a cycle (rather than mid-cycle) helps you feel refreshed instead of groggy. Most adults do best with 5–6 cycles (7.5–9 hours), plus ~15 minutes to drift off.

Kids tips

🧸

Enter the school wake-up time to find bedtimes that give a full night of complete cycles.

💡

School-age kids need more sleep than adults — aim for the longer (6-cycle) options.

🎯

A consistent bedtime, even on weekends, keeps the body clock steady and mornings easier.

How It Works

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Process

The tool processes your data instantly in your browser using JavaScript. No server, no waiting.

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Get your result instantly. Nothing is stored after you leave the page — complete privacy.

Why use ours?

✓Completely free — no hidden costs, ever

✓No account, email, or login required

✓Files never leave your device

✓No file size limits whatsoever

✓No watermarks on any output

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Frequently Asked Questions

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