[Event] Ask the Experts: Tax Law Changes - One Big Beautiful Bill

To determine how much social security was taxed, look at line 6b of Form 1040, which equals the taxable amount of your social security benefits. 

Your second question has a more nuanced answer because income taxes are assessed on a graduated level. One approach is to consider your marginal tax rate, which is the tax rate applied to the next dollar of income you earn. Look up your taxable income on line 15 of Form 1040. Compare that number to the tax brackets shown in the picture below. For example, if your taxable income was $95k, the tax rate would be 22%. 

Another way you could look at it is to consider your total tax on line 24 of Form 1040 divided by your taxable income on line 15. This gives you your effective tax rate, which is the actual percentage of your taxable income that you pay in federal taxes.

I hope this info helps. Thanks for your question!