Whoop, Inc. is a Boston-based wearable technology company founded in 2012 by Harvard athlete Will Ahmed and his co-founders, best known for its screenless, subscription-based health tracker that measures strain, recovery, and sleep—a favorite among elite athletes like LeBron James and Cristiano Ronaldo. The device collects data on heart rate variability, resting heart rate, and respiratory rate to generate a daily recovery score, and has evolved through major milestones like the Whoop 4.0 (2021), the Stress Monitor feature (2023), and an OpenAI-powered "Whoop Coach." The company has attracted massive investment, raising $200 million from SoftBank in 2021 (at a $3.6 billion valuation) and a $575 million Series G in April 2026 that pushed its valuation to $10.1 billion with backers like Abbott and the Mayo Clinic. However, in May 2025, Whoop faced public backlash over upgrade fees for its 5.0 and MG devices that contradicted earlier promises of free hardware upgrades, prompting the company to reverse course and offer complimentary upgrades to long-term members. More recently, in September 2025, Whoop launched "Advanced Labs" to integrate clinical blood test data with wearable metrics, further cementing its role in proactive health monitoring.