Sleep Calculator
Free sleep calculator based on 90-minute sleep cycles. Enter your bedtime to see optimal wake times, or enter your wake time to see when to go to bed. Accounts for 15 minutes to fall asleep. Includes age-based sleep recommendations and sleep quality tips.
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How to Use Sleep Calculator
- 1Choose mode: 'When to wake up' or 'When to go to bed'.
- 2Enter your bedtime or desired wake time.
- 3View recommended times based on sleep cycles.
- 4Select the option that gives you enough cycles.
Frequently Asked Questions
It calculates based on 90-minute sleep cycles. Waking between cycles (rather than mid-cycle) helps you feel more refreshed.
Adults need 7-9 hours (4-6 sleep cycles). Teens need 8-10 hours. Children need 9-12 hours depending on age.
You may be waking mid-cycle. Try adjusting your wake time by 15-30 minutes to align with a cycle boundary.
The Sleep Calculator is an online tool that lets you find optimal bedtime or wake time based on 90-minute sleep cycles. It is part of NexTool's collection of free tools designed to help you work faster and more efficiently.
The Free plan includes 10 tool uses per day. Some features require an account or a paid plan. Check the controls on the tool page and Pricing for the applicable limits.
Yes, the Sleep Calculator is fully responsive and works on any device with a modern web browser, including smartphones, tablets, laptops, and desktops. No app installation is needed.
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About Sleep Calculator
Free sleep calculator based on 90-minute sleep cycles. Enter your bedtime to see optimal wake times, or enter your wake time to see when to go to bed. Accounts for 15 minutes to fall asleep. Includes age-based sleep recommendations and sleep quality tips.
Use the controls shown by Sleep Calculator to generate and review your result. Available features and usage limits depend on your plan. Check the tool's instructions and privacy information before submitting data.
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Add Sleep Calculator to your website. Paste the code below into your HTML. The iframe auto-resizes to fit the tool content.
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