About this site

Welcome to the NIST Time and Frequency Division, an operating unit of the Physics Laboratory of the National Institute of Standards and Technology (NIST), an agency of the U.S. Department of Commerce. We are located in Boulder, Colorado at the NIST Boulder Laboratories (shown at right, click on image to see larger image).

Our mission includes:

• Maintaining the primary frequency standard for the United States.
• Developing and operating standards of time and frequency.
• Coordinating United States time and frequency standards with other world standards.
• Providing time and frequency services for United States clientele.
• Performing research in support of improved standards and services.

Precise time and frequency information is needed by electric power companies, radio and television stations, telephone companies, air traffic control systems, participants in space exploration, computer networks, scientists monitoring data of all kinds, and navigators of ships and planes. These users need to compare their own timing equipment to a reliable, internationally recognized standard. NIST provides this standard for the United States.

See also legal notes about this site.

Contact Information

National Institute of Standards and Technology
Time and Frequency Division 847
325 Broadway
Boulder, CO 80305-3328
(303) 497-3295
(303) 497-6461 (fax)

Please send us email if you have questions, comments, corrections, or suggestions regarding the NIST Time and Frequency division web site.