Time Outside Is Good

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Daylight Ledger

A running record of the time you spend outside and the cover you wear while you're there. Two hours a week in green space is the threshold where people start reporting better health and wellbeing — this keeps score of yours, and of the shade, cloth and SPF that let you keep going back.

Today's sun

This week0of a 120 min goal
Streak0days in a row outside
Peak UV todayestimated, clear sky
Cover wornof your logged sessions
You're looking at a few sample entries so nothing starts empty. Clear them whenever you're ready to log your own.

Log time outside

Takes about twenty seconds
Cover you wore
How settled do you feel now
Wound upSettled
And how much energy
FlatCharged

Reapply clock

Two-hour rule
Clock not running Start it when you put sunscreen on

A full-body coat is about 30 ml — a shot glass. Face, ears and neck take roughly a teaspoon between them. Most people apply about a quarter of that, which is why the clock matters more than the number on the bottle.

Today so far

Worth knowing

Shadow ruleWhen your shadow is shorter than you are tall, the sun is high enough to burn you quickly. Long shadow, low risk.

80%of UV comes through thin cloud. An overcast day is a cooler day, not a safer one.

×1.8Fresh snow nearly doubles the UV reaching your face. Water adds about a quarter, dry sand about a sixth.

UPF 50fabric lets through a fiftieth of the UV that hits it, and it does not wear off at hour two.

Where the day's UV sits

Clear-sky model, local solar time

Your inputs

Time to redden

Minutes outside, by week

Goal line at 120 min

Milestones

This week

All time

Recent sessions

Today's prompt

These prompts ask what your body did and what you noticed — never how it looked. Sun care lasts longer when it reads as looking after yourself rather than fixing yourself.

Earlier entries

What this is

A tracker that runs in your browser. There is nothing to install and no account to make. Everything you enter is stored on this device only -- the one you’re using right now — clearing your browser data clears the ledger with it.

How the numbers are worked out

UV is modelled from your latitude, the date and the sun's angle, then adjusted for cloud and surroundings. Time-to-redden uses standard minimal erythema doses by skin type. These are estimates for planning, not measurements.

Not medical advice

Nothing here diagnoses or treats anything. A doctor or dermatologist should be your first call about a mole that has changed, a burn that blisters, or how much sun is right for you.