(Tested with ENDF/B-VIII.0 Data)

PREPRO output is compatible with FORTRAN, C, and C++ code

Release: 07 September 2021 (2021-1 version)
Updated: 08 October 2021 (2021-2 version)
Reference: D.E. Cullen, PREPRO 2021 - ENDF/B Pre-processing Codes,
Technical report IAEA-NDS-0238, September 2021, International Atomic Energy Agency, Vienna , Austria.

Developed by: Dermott E. Cullen
National Nuclear Data Center, BNL, alumnus; Nuclear Data Section, IAEA, Vienna, alumnus; University of California, LLNL, retired

What is PREPRO?

The ENDF/B Pre-processing codes (PREPRO), is a collection of 18 computer codes, which are designed to convert ENDF/B formatted neutron and/or photon data from the originally distributed form to a form in which the data can be used in applications.

These codes also allow you to view the data, on-screen and/or hardcopy. The ENDF/B Pre-Processing Codes run on virtually ANY Computer. Pre-Processing code output is Completely FORTRAN, C and C++ Compatible.

Here you can download the codes and documentation for ANY computer. In addition, the codes are also distributed via GitHub.

Here you can also download the BEST Input Parameters to use with each code.


Recent changes in ENDF-6 Format and procedures, as well as the evaluations themselves makes it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2021 (2021-1 Version) to accurately process current ENDF/B-VIII.0 evaluations. The present codes can handle all existing ENDF/B-VII.0, VII.1 and VIII.0 evaluations.

Documentation is NOT included with downloaded codes for each computer. You must download documentation separately.

Download Codes
Download Codes from GitHub
Download Documentation
Download BEST Input Parameters
PREPRO 2021 History: Check for changes that may affect you

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