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Interoperable Randomness Beacons

NIST Randomness Beacon (Prototype Implementation; Version 1.0) -- Replaced by Version 2.0


This prototype implementation generates full-entropy bit-strings and posts them in blocks of 512 bits every 60 seconds. Each such value is sequence-numbered, time-stamped and signed, and includes the hash of the previous value to chain the sequence of values together and prevent even the source to retroactively change an output package without being detected.

Currently implemented calls are listed below. Users submitting a request need to provide the record generation time in POSIX format (number of seconds since midnight UTC, January 1, 1970 (see for more information and for an online timestamp converter.)

Current Record (or next closest):<timestamp>

Previous Record:<timestamp>

Next Record:<timestamp>

Last Record:

Start Chain Record:<timestamp>

If a request for a next or previous record results in no record found, a 404 response is returned.


The data source schema for the NIST Beacon 1.0 REST API described above can be viewed by clicking here.

Note: Not all browsers will display this file appropriately, you may get better results by saving the file locally and using an editor of your choice.


NIST Beacon 1.0 used an X.509 certificate with the Federal Common Policy CA as the ultimate root authority for some of the records. The certificate is available here

The Beacon Signing Key changed in May of 2017. Not all records will successfully validate.


The example application below uses the REST API described above to navigate the data.

To visit an arbitrary time value please click on the input control containing the date and time value to display a calendar to select the desired value.


Reach us at:

René Peralta

Harold Booth

Luís T. A. N. Brandão

John Kelsey

Carl Miller


Security and Privacy: cryptography

Created June 03, 2019, Updated May 16, 2024