how does google know how busy a place is

Google determines how busy a place is primarily by analyzing aggregated and anonymized location data from users who have opted in to Google Location History. When people have location services enabled on their phones and use Google Maps or other Google services, Google collects anonymous location signals from their devices to estimate how many people are present at a particular location. More devices detected generally means a busier place. Google uses this real-time location data to track foot traffic patterns and movement in and out of places like stores, restaurants, parks, and other public venues. It also leverages historical data on busyness patterns to predict busy times, for example, knowing a store is usually busiest on Saturday afternoons. In addition to location data, Google incorporates user- generated content such as social media check-ins, reviews mentioning wait times, and photos that show crowds. Algorithms analyze all these data points along with external factors such as weather or local events to provide accurate, dynamic busyness information displayed on Google Maps as popular times and live busyness updates. To protect user privacy, Google ensures the data is anonymized and uses privacy-preserving techniques so individual users cannot be identified. Busyness data is not calculated for residential places and is only shown where there is sufficient aggregated data. In summary, Google uses a combination of anonymized location data from phones, historical traffic patterns, user-generated information, and advanced algorithms to estimate and display how busy a place is at any given time.