Accuracy of hmF2 estimations, including IRI-2020 options and ionograms validated parameters, compared to ISR measurements at Millstone Hill

•The accuracy of different formulas for hmF2 estimation is investigated using Millstone Hill ISR data.•SHU-2015 model performs better in any condition even compared to the formulas fed by validated data.•BSE-1979 provided reasonably good results, while AMTB-2013 does not work satisfactory during night.•SHI-1955 and BSE-1979 formulas fed by validated data can be used for trend analyses at night.