According to the 2010 Russian Census (the most recent comprehensive enumeration), 80.9 % of Russia’s population self-identified as ethnic Russians. Of those, ≈ 99 % consider themselves part of the Slavic ethnolinguistic group.
0.809 × 0.99 ≈ 80.1 % of Russia’s total population are Slavic-identified ethnic Russians.
The 2020 census was postponed to 2021 and results remain partially unpublished; demographics may have shifted slightly due to migration and differential birth rates.