Financial support of the Grant Academy of Czech Republic of project "Advanced Experimental and Theoretical Approaches to Size-Dependent Phase Diagrams of Nanoalloys" (GA17-15405S) is gratefully acknowledged. This research has also been financially supported by the MEYS CR under the project CEITEC 2020 (LQ1601) and the Horizon 2020 Research and Innovation Program under the grant agreement no. 810 626 (SINNCE).

This dataset contains the raw experimental data to the article Sopou��ek et al., Continuous Flow Synthesis of Iron Oxide Nanoparticles Using Water-in-Oil Microemulsion, Colloid Journal, 2020, Vol. 82, No. 6, pp. 727���734.