Employee commuting - Scope 3, Category 7 - is one of the most widely reported and least verified categories in corporate carbon accounting. Most companies estimate it from an annual survey. Almost none measure it. The Commute Grand Prix turns that gap into a week of action. From 20-27 September, anyone, anywhere, can take part at no cost: download the Ecomiles app, log your daily commute, and watch your verified emissions savings accumulate on a live global leaderboard - as an individual and on behalf of your employer. Employers can sponsor rewards for their own teams at no cost to participants. The challenge closes on 26 September with a 45-minute online session, open to all, where Ecomiles publishes a first read of the week's data alongside its wider dataset of more than one million GPS-verified trips across Brazil, Spain, Portugal, Finland and Japan - and what the distance between measured and survey-estimated commuting means for anyone reporting Category 7. Ecomiles is a Certified B Corporation whose methodology carries KPMG limited assurance. Free to join. No purchase necessary.