Earlier this year the Estonian Bureau of Statistics released a report detailing the number of Estonian speakers in Estonia. At the beginning of 2016 there were 883,707 people in Estonia who spoke Estonian as their mother tongue, i.e. 68.4% of the population. The report is a good read covering the different regions.
To read the full report (in Estonian) please click here: Kui palju räägitakse Eestis eesti keelt?