companies

WHOOP Inc.

Subscription-only fitness wearable that scores sleep, strain and recovery, with an in-app AI coach for daily training guidance.

WHOOP makes a screenless wrist strap that tracks heart rate, sleep stages, and daily strain around the clock, translating the readings into a nightly recovery score. Founded in 2012 by Will Ahmed while he was a Harvard undergraduate, the Boston company sells no device outright — every WHOOP ships bundled with a required membership, and the hardware itself stays on loan to subscribers for as long as they keep paying. In 2023 WHOOP layered a conversational assistant, WHOOP Coach, on top of its metrics, fine-tuning OpenAI's GPT-4 on anonymized member data so it can answer questions like whether a hard run today will hurt tomorrow's recovery. The WHOOP 5.0 and WHOOP MG straps, released in 2025, extended battery life and added a medical-grade tier with blood-pressure-adjacent readings. Athletes including Cristiano Ronaldo and LeBron James are both users and investors; the company closed a $575 million Series G in 2025 at a $10.1 billion valuation, bringing total funding past $900 million.

Founded

2012

Headquarters

Boston, United States

Sector

hardware