WHOOP & OURA

I've now collected roughly two months of data. I kept the raw data in a simple spreadsheet, recording a few basic measurements each day: sleep duration and stages (Light, REM, Deep, and Awake/tossing and turning), heart rate metrics such as Resting Heart Rate (RHR) and Heart Rate Variability (HRV), and the sleep score reported by each app.

I logged these numbers every morning as soon as I woke up, allowing me to compare the different apps and, more importantly, correlate their measurements with how I actually felt that morning.

You can find the raw data in this spreadsheet.

After two months of tracking sleep with Oura, Whoop, 8Sleep and Apple Watch , I found a clear hierarchy:

Oura and Whoop Tier 1: Both produced high-quality, broadly consistent sleep tracking, with scores that usually matched how the author felt the next morning. 8Sleep acceptable: Its tracking was less convincing and correlated less strongly with Oura and Whoop. AutoSleep poor: Its scores varied wildly, showed little correlation with how the author felt, and barely correlated with Whoop (0.14), leading the author to characterize it as essentially random. Key data findings

Sleep score correlation:

Whoop vs Oura: 0.65

Oura also had the most useful dynamic range. It rarely gave perfect scores, whereas Whoop, 8Sleep, and especially AutoSleep tended to cluster toward very high scores.

Heart-rate tracking: Oura, Whoop, and Apple Watch showed very strong agreement in nighttime resting heart rate, despite 8Sleep having to estimate heart rate indirectly through the mattress.

Interestingly, RHR didn't strongly correlate with sleep scores. Whoop showed only a very small relationship (~0.13), while Oura showed essentially none.

**Exercise showed up in the data ** Over the 60-day period, regular cardio and HIIT appeared to produce measurable improvements:

RHR: ~51 → ~48 bpm HRV: ~49 → ~54

The author notes that Whoop's HRV readings were consistently about 5 points higher than Oura's, likely because the two systems calculate HRV differently.

The biggest takeaway: sleep really matters

I found a strong relationship between sleep quality and productivity. Poor sleep meant less energy, creativity, courage, and ability to work effectively. Good sleep enabled long periods of highly productive work.

The effect wasn't simply about the previous night's sleep it appeared to reflect accumulated sleep debt over several days. One bad night was manageable, but several consecutive poor nights had a noticeable impact.

**Final recommendations **Tracker Verdict Main reason Oura 10/10 Best overall tracking, excellent overview, great data presentation Whoop 9.5/10 Extremely reliable, comprehensive, and much more convenient to wear 8Sleep Average Sleep tracking wasn't sufficiently reliable AutoSleep Avoid Scores appeared highly inconsistent and poorly correlated

**Bottom line: **Choose Oura if tracking accuracy and data presentation are your top priorities. Choose Whoop if you want nearly as good tracking with a significantly more convenient wearable.