Stars that have precise, accurate and independent measurements of their fundamental properties will be essential to quantify the precision and accuracy of stellar parameters in the PLATO data products. The benchmark stars work package WP125500 have identified several types of star that will be useful for benchmarking PLATO data products, e.g., eclipsing binaries, transiting hot Jupiter systems, nearby stars with directly measured angular diameters, etc. In this talk, I will review the different types of benchmark star and give some preliminary results for the number and properties of benchmark stars in the LOPN1 and LOPS2 fields.