All IUCr Journals are tracked by Thomson Scientific (ISI). A summary of the impact factors for IUCr Journals is given below.
| 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | |
| Acta Crystallographica Section A | 1.806 | 2.146 | 1.601 | 1.491 | 1.749 | 1.417 | 1.558 | 1.829 | 1.791 |
| Acta Crystallographica Section B | 1.463 | 1.612 | 1.700 | 1.734 | 1.955 | 2.026 | 3.643 | 5.418 | 1.910 |
| Acta Crystallographica Section C | 0.459 | 0.577 | 0.581 | 0.543 | 0.570 | 0.659 | 0.828 | 0.728 | 0.777 |
| Acta Crystallographica Section D | 2.118 | 2.244 | 2.935 | 3.067 | 2.124 | 1.760 | 2.208 | 1.693 | 1.401 |
| Acta Crystallographica Section E | 0.453 | 0.491 | 0.581 | ||||||
| Acta Crystallographica Section F | |||||||||
| Journal of Applied Crystallography | 1.988 | 1.569 | 1.901 | 1.752 | 2.583 | 1.871 | 2.324 | 3.534 | 5.248 |
| Journal of Synchrotron Radiation | 1.688 | 1.874 | 1.114 | 0.924 | 1.519 | 0.885 | 1.144 | 1.919 | 2.392 |
* Acta Crystallographica Section F is covered by ISI, but as a new journal will not receive an impact factor until 2007 impact factors are published.
Impact factors are generally calculated based on a three-year period. For example, the 2005 impact factor for a journal would be calculated as follows:
where A = number of times articles published in 2003-2004 were cited in tracked journals during 2005 and B = number of articles published in 2003-2004.