I have a question regarding tax in the Netherlands. I have a gross monthly salary of 3,500. I am allowed to enter the 30% tax ruling (young employee with masters). Then what is my monthly net income? I tried the site https://thetax.nl and got a monthly net salary of 3,042. However, on https://www.blueumbrella.nl/income-tax-return/income-tax-calculator/ I only get a monthly net salary of 2,723. Hence I am a bit confused :). Is there any official site to get reliable data?