Welcome to PeMS
Welcome to the Caltrans Performance Measurement System (PeMS). The traffic data displayed on the map is collected in real-time from over 39,000 individual detectors. These sensors span the freeway system across all major metropolitan areas of the State of California.
PeMS is also an Archived Data User Service (ADUS) that provides over ten years of data for historical analysis. It integrates a wide variety of information from Caltrans and other local agency systems including:
To use this site, you must apply for an account. Registering only takes a few minutes. Accounts are typically approved within one to two business days.