Why are some journals with low impact factor indexed in Web of Science while others with a relatively higher impact factor are not?

Question

I'm a researcher in mathematics. While looking for journals in my field, I found out while some journals with a low impact factor are indexed in Web of Science, another Springer journal with a higher impact factor is not.

Journal indexed in Web Of Science (lower impact factor)

Journal indexed in Web Of Science (lower impact factor)

Springer journal not indexed in Web Of Science (higher impact factor)

I couldn't find an explanation, except that the Springer journal hasn't requested to be indexed in Web of Science yet. Is there another explanation of what makes some journals get indexed by Web Of Science while other journals with relatively higher impact are not?

Answer 1

There are no journals with a relatively higher impact factor that are not indexed in Web of Science. That's because you need to be indexed in Web of Science to get an impact factor. Note the impact factor is calculated by Clarivate, which is the entity that owns Web of Science.

You could calculate your own impact factor (which is not too difficult, because the methodology is both simple and known), but it won't be the impact factor.

I don't know where you got the impact factor of the Springer journal, but if it's not indexed by Web of Science, it doesn't have one. Springer is (honestly) not reporting an impact factor for that reason. See here for an example of a Springer journal with an actual impact factor.

A number of BMC and SpringerOpen journals have impact factors and some journals are being tracked by Clarivate Analytics and will receive their impact factor in due course. For any journal to have an impact factor it must be tracked by Clarivate Analytics for two years (for more information on how impact factors are calculated, please see here).

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