APR calculator on Ethereum staking

Question

my question is - how to get actual APR on Ethereum for delegators? So, knowing the APR we'll be able to estimate the reward for users.

Answer 1

Well depending of how you distribute rewards, but you should probably store rewards distributed and available to users and then do something like:

   uint256 currentAprNumerator = reward * 36500;
    uint256 currentAprDenominator = stakedAmountOf[account] * stakingDurationInDays;

    if (currentAprDenominator == 0) {
        return 0;
    }

    uint256 currentApr = currentAprNumerator / currentAprDenominator;