  The large dataset of about 3000 fb$^{-1}$ that will be collected by both the
ATLAS and CMS experiments at the High Luminosity LHC (HL-LHC) will be used to
measure Higgs boson properties in detail. Studies based on current analyses
have been carried out to understand the expected precision and limitations of
these measurements. The large dataset will also allow for better sensitivity to
Higgs boson pair production processes and the Higgs boson self-coupling. This
proceeding presents the prospects for the precise measurements of the Higgs
boson properties and Higgs boson pair production with the ATLAS and CMS
detectors at the HL-LHC.
