Understand that gross income can be different from taxable income. For example, Ida has a gross income of $45,000, and contributes $4,500 to a tax deferred retirement plan and $1,500 to a Health Savings Account. Ida’s taxable income is reduced to $39,000.
Adjustments to income can decrease or increase AGI. Income such as alimony (if the divorce decree is after 12/31/2018), unemployment income, and self-employment income can increase AGI. Common examples of items that can decrease AGI include educator expenses (K-12 teachers), contributions to a traditional IRA, student loan interest, and tuition expenses. For a full list if adjustments that can increase or decrease income, see Schedule 1 of Form 1040 https://www.irs.gov/pub/irs-pdf/f1040s1.pdf
For tax filing years 2020 and 2021, there is a special above-the-line deduction of up to $300 in 2020 and in 2021 up to $300 for single or $600 married filing jointly for cash gifts to charity. This means that a taxpayer can take the standard deduction (most Florida tax filers do not itemize) and still take this special charitable deduction and reduce their AGI.
Source : ufl.edu