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The Iris Exchange (IREX) was initiated at NIST to expand iris recognition capabilities and support a marketplace of iris-based applications based on standardized interoperable iris imagery. The work was initially conducted to support of the ISO/IEC 19794-6 standard and later the ANSI/NIST ITL 1-2007 Type 17 standard. Subsequently IREX has included dedicated activities in support of: iris image quality assessment and standardization (IREX II); performance of one-to-many algorithms (IREX III + IV); compression (IREX IV); instructions to personnel involved in iris image collection (IREX V) and time dependence of iris recognition (IREX VI).







The data used in IREX comes from publicly available datasets and from operational data provided by various government and commercial entities. The publicly available data sets may be procured from the original sources; in general, NIST does not have license to redistribute any of the public datasets that are used in IREX. The operational data has been provided by the data owners under the condition that it will not be redistributed by NIST. Hence, in general, the IREX program cannot provide datasets to the research community. A list of the datasets used in the IREX effort can be found here .

IREX 10 (Ongoing)

IREX 10 is a continuing evaluation of automated iris recognition technology on sequestered test data. As an ongoing evaluation, developers may submit their software at any time.  The results are available on the IREX 10 results page which is updated as algorithms are submitted and evaluated.


IREX IX continues along the path of IREX III & IV as an evaluation of iris recognition algorithms for use in large-scale deployments. IREX IX will explore:          

  • Verification: One-to-one matching
  • Identification: One-to-many matching
  • Effects of illumination wavelength: visible through the near infrared, both within and between wavelengths
  • Effects of off-angle images: such as might be expected from captures on handheld mobile devices
  • Forensic applications: images from cameras not designed for iris recognition 

As before, the primary evaluations will be carried out on sequestered data from US government sources – this assures a level playing field for all. Secondary evaluations on publicly available datasets will also be carried out – this aids developers by enabling reproduction of evaluations.


IREX VIII, PIV Support,  produced a documentary profile that was incorporated into NIST Special Publication 800-76-2, Biometric Specifications for Personal Identity Verification that is available at   That publication supports the Personal Identity Verification (PIV) standard for Federal Employees and Contractors, FIPS 201-2 as described in the documents available at


IREX VII was a planned activity intended to provide a  framework for communication and interaction between components in an iris recognition system by introducing layers of abstraction that isolate underlying vendor-specific implementation details from application programs in the system.   IREX VII was never implemented.  


In response to studies reporting an aging effect in iris recognition, NIST initiated the IREX VI project to independently assess the stability of the iris for long term recognition, and to track other research in the area. The IREX VI homepage includes NIST research on longitudinal analysis of iris recognition systems.


IREX V provides best practice recommendations and guidelines for the proper collection and handling of iris images. IREX V documents are available on the IREX V homepage


IREX IV continues along the path of IREX III as an evaluation of one-to-many iris recognition for large-scale applications. IREX IV was initiated to serve two purposes: 1) to explore the potential for using cost functions for application-specific algorithm optimization; and 2) to support the ISO/IEC 19794-6 standard by defining a compression profile for the compact representation of iris images.

NIST is happy to announce the availability of first part of the IREX IV evaluation report, NIST Interagency Report 7949. The second and final part, NIST Interagency Report 7978,focuses on compression profiles for iris image compression


NIST concluded the IREX III evaluation of one-to-many iris algorithms in April 2012. IREX III was the first independent and public test of iris identification search technologies. It used millions of images to validate results published in the academic literature that iris is a very powerful biometric. The final report and a chronology of the test are given on the IREX III home page: 

IREX II IQCE (Iris Quality Calibration and Evaluation)

IREXII IQCE aims to evaluate the effectiveness of image quality assessment algorithms (IQAAs) that produce a scalar overall image quality in predicting the recognition accuracy of particular comparison algorithms (from the supplier of the IQAA), and of other algorithms. Furthermore, per the IREX I result that quality scores are not immediately interoperable, IQCE will establish a score calibration procedure for IQAAs.


IREX I was being conducted to address two issues: First is how far compression can be pushed before the accuracy of leading commercial matching algorithms begins to degrade. Second, the accuracy of iris images in compact polar form when it is prepared by one supplier and verified later by another. The program supports identity management applications where compact size and interoperability are of primary concern. These include federated identity credential or network-based applications.


Subscribe to the irex+subscribe [at] (IREX mailing list) to receive emails when announcements or updates are made.


Created June 17, 2010, Updated February 1, 2024