Julian - there are indeed many journals with an IF less than one. There are several reasons i.e. it is a newly established journal - and it depends on the ranking criteria - espedially with larger companies such as SCImago and Clarivate. They sometimes exclude personal citation - so that doesn't factor - and the lower the rank of the journal - often the less likely that submitting authors have previous citations to draw upon.

Hi Julian,

The formula for calculating an impact factor is:

IF(2019) = Number of citations the journal received in 2019 for articles published in 2018 and 2017 divided by the total number of articles published by the journal in 2018 and 2017

So to get an impact factor of less then 1, the journal received less citations in that year for papers that were published in the previous two years than the number of articles it published in those two years.

Even if every author cited their paper, this would only count if the paper was published in the previous two years.

Lets look at an example with self citation. If you published a paper in 2017, you would need to cite it in 2018 or 2019 for the citation to count towards the impact factor. If you cite it in 2020, it will not be counted towards the impact factor.

I hope that makes sense. let me know if you have any other questions.

Hi,

Many journals, especially in the humanities, and those published in Non-English languages, have an impact factor less than one, and new journals too. It depends on the number of citations a journal gets in relation to the number of publications in the passed two years, or an accumulated IF of the last five years. The IF counting starts with a zero.