Free planner · 3 minutes · stays on your device
The Light Map
Your body keeps time with light. Put your real sunrise, your sleep and your week on one 24-hour sun dial, and see when light, coffee and dimmer evenings do the most for you.
Where are you?
Everything is calculated in your browser. Your location and times are never sent anywhere.
- Sunrise
- 06:09
- Sunset
- 18:19
- Solar noon
- 12:14
- Daylight
- 12h 10m
- Daylight
- Twilight
- Night
- Light window
- Dim evening
- Last coffee
- Your workday sleep
- Your free-day sleep
Your light window
06:45 to 08:45. The first two hours after waking are when your clock responds most to light. Get outside, or into the brightest room you have. [1]
Today the sun is up for 120 of those minutes.
Last coffee
By 17:15. In a lab study, a strong dose of caffeine taken even six hours before bed cut measured sleep by more than an hour, and people did not notice. [3]
Dim the evening
From 20:15. Experts recommend keeping evening light low for at least three hours before bed, and the bedroom as dark as you can. [2]
Dark mornings this year
On about 171 days a year (mid Sep to early Mar) your workday alarm goes off before sunrise. Those are the mornings to plan bright light for.
Your chronotype
04:19
Mid-sleep on free days, corrected for catch-up sleep: 04:19. On the Munich ChronoType scale, the later this time, the later your body clock runs. [4]
Social jetlag
1 h 30 min
1 h 30 min: the gap between the middle of your sleep on workdays and on free days. [5]
Like flying one time zone east every Monday and back every weekend.
Sleep you actually get
Workdays 7 h 30 min, free days 8 h, weekly average 7 h 39 min. Most adults need 7–9 hours, the shaded band. [7]
Why light runs the show
Camping study
After a week of only natural light outdoors, people's internal clocks moved about two hours earlier and sleep followed, while total sleep stayed about the same. [1]
Expert consensus
Bright light by day (daylight first), dim light for at least three hours before bed, and darkness at night best support sleep and alertness in healthy adults. [2]
Coffee timing
Caffeine six hours before bed still shortened sleep by more than an hour in a lab study. People underestimated the effect. [3]
Free with the Sunrise Letter
Your Light Poster and 14-day reset
Your dial and your times on one printable page, plus daily reminders for two weeks.
- A printable 24-hour Light Poster with your windows
- Daily calendar nudges for 14 days: morning light and dim evenings
- A two-weekend plan to shrink your social jetlag
- Then the Sunrise Letter: calm, useful longevity news, only when there's something worth saying
Sources
- Wright KP Jr, McHill AW, Birks BR, Griffin BR, Rusterholz T, Chinoy ED. Entrainment of the human circadian clock to the natural light-dark cycle. Curr Biol. 2013;23(16):1554–1558. doi:10.1016/j.cub.2013.06.039
- Brown TM, Brainard GC, Cajochen C, et al. Recommendations for daytime, evening, and nighttime indoor light exposure to best support physiology, sleep, and wakefulness in healthy adults. PLoS Biol. 2022;20(3):e3001571. doi:10.1371/journal.pbio.3001571
- Drake C, Roehrs T, Shambroom J, Roth T. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013;9(11):1195–1200. doi:10.5664/jcsm.3170
- Roenneberg T, Wirz-Justice A, Merrow M. Life between clocks: daily temporal patterns of human chronotypes. J Biol Rhythms. 2003;18(1):80–90. doi:10.1177/0748730402239679
- Wittmann M, Dinich J, Merrow M, Roenneberg T. Social jetlag: misalignment of biological and social time. Chronobiol Int. 2006;23(1–2):497–509. doi:10.1080/07420520500545979
- Roenneberg T, Allebrandt KV, Merrow M, Vetter C. Social jetlag and obesity. Curr Biol. 2012;22(10):939–943. doi:10.1016/j.cub.2012.03.038
- Hirshkowitz M, Whiton K, Albert SM, et al. National Sleep Foundation's sleep time duration recommendations: methodology and results summary. Sleep Health. 2015;1(1):40–43. doi:10.1016/j.sleh.2014.12.010
- NOAA Global Monitoring Laboratory. General Solar Position Calculations (equations used for the sunrise, sunset and twilight times on this page).
Last reviewed: 2026-11-05
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