Systematic Reviews (SRs) hold promise for implementing the 3Rs in animal sciences: they can retrieve available alternative models, help refining experiments, and identify insufficiencies, or an excess of, scientific knowledge on a particular topic. Unfortunately, SRs can be labour- and time-intensive, especially the reference screening and data extraction phases. Fortunately, there are several software tools available that help make screening faster and easier. However, it is not always clear which features the tools offer. Therefore, a feature analysis was performed to compare different reference screening tools as objectively as possible. This analysis enables researchers to select the most appropriate tool for their needs. Fifteen different tools were compared: CADIMA, Covidence, DistillerSR, Endnote, Endnote using Bramer's method, EROS, HAWC, Microsoft Excel, Excel using VonVille's method, Microsoft Word, Rayyan, RevMan, SyRF, SysRev.com, and SWIFT Active Screener. Their support of 21 features was tested. Features were categorised as mandatory, desirable, and optional. DistillerSR, Covidence, and SWIFT Active Screener are the tools that support all mandatory features. These tools are preferred for screening references, but none of them are free. The best scoring free tool is Rayyan, which lacks one mandatory function: distinct title/abstract and full-text phases. The lowest scoring tools are those not specifically designed for SRs, like Microsoft Word and Endnote. Their use can only be advised for small and simple SRs. A well-informed selection of SR screening tools will benefit review quality and speed, which can contribute to the advancement of the 3Rs in animal studies.