Set your details below to see today's light window.

Find your daylight balance

Estimate how much morning outdoor light — and evening red or amber light — can help offset your daily screen time.

Your location

Used only to estimate today's day length. Only your latitude is kept, and only on this device, so you don't have to re-enter it. If you type a city or ZIP, that text is sent to a free lookup service to find its latitude.

Tap "Use my location", or enter your city or ZIP.

City or ZIP code

Or enter latitude directly

Latitude (−90 to 90)

Computer / laptop screen time

Approximate hours per day, typically at arm's length.

6 hrs

Phone / tablet screen time

Approximate hours per day. Weighted higher — phones sit closer to the eyes and are often brighter relative to surroundings.

4 hrs

Today's sky

Cloud cover lowers outdoor light intensity, so cloudier days call for a bit more time outside.

Your estimated light plan

🌅

Morning outdoor light

— minutes

Best taken within about an hour of waking. Morning light helps set your internal clock, supporting alertness during the day and easier sleep onset at night.

Why morning light matters

Bright light early in the day is one of the strongest cues your body uses to anchor its circadian rhythm — the internal clock that governs sleep, energy, and hormone timing.

Why evening screen light can disrupt sleep

Screens emit a lot of blue-enriched light, which can suppress melatonin and delay the body's signal that night has arrived. Warmer, dimmer red or amber light in the evening is far less disruptive.