90-Day Sleep Log

A sleep tracker measures your heart. It has no idea you had an espresso at 4 p.m., argued at dinner, or trained hard at noon. The single most useful sleep record you can keep is the one that puts your body's numbers and your day's events on the same line — and reads them together.

That is this log. Ninety nights, one line each, 90 seconds every morning with your coffee. Fill it consistently and the patterns stop being a feeling and become a finding.

WHAT'S IN THE LOG (19 pages, printable PDF)

THE FIELD GUIDE — every one of the 13 columns explained, with the honest way to fill each. Works with or without a wearable: dash the four tracker columns and the rest still finds every pattern.

13 WEEKLY PAGES — ONE LINE PER NIGHT Bed and wake times, minutes to fall asleep, night wakes, your tracker's four numbers (score, HRV, resting HR, deep sleep), last caffeine, alcohol, exercise, how you actually feel in the morning (1–5), and a notes column for the one-offs. A progress bar fills week by week; milestone badges mark days 30, 60 and 90.

THE FRIDAY REVIEW — five minutes each week: best night, worst night, the pattern you suspect (phrased as a bet), and the one change you will test next week.

THE WEEKLY EXPERIMENT — change one thing, mark the day you changed it, and name the number that should move if it works.

3 MONTHLY TREND PAGES — hand-plot your weekly averages: minutes-to-sleep, morning feel, and one tracker metric. Four dots, connect the line, watch it move.

THE DAY-90 VERDICT — the payoff page. Copy your Week 1 and Week 13 averages side by side and let the change column say what 90 nights of evidence proved.

THE METHOD Trends, never single nights. One variable at a time. Blanks are allowed — a gap is data, not a reason to restart. Your own consistent estimate is a legitimate instrument, tracker or not.

WHO IT IS FOR Anyone who has stared at a sleep score and thought "but why?" — and wants the answer in their own handwriting. Oura, Whoop, Garmin and Apple Watch owners get the fullest picture; everyone else still gets the pattern.

Instant download. Print the pages you need, or fill them on a tablet. From the maker of the free Deep Sleep Protocol at sleepmetricscience.com.

(General education, not medical advice. Loud snoring, gasping awake, or exhaustion a good log cannot explain are reasons to see a doctor.)