Plain-language definition
Start with taxable sources included in total income, then subtract eligible adjustments listed on Schedule 1. On the current Form 1040 structure, total income is on line 9, adjustments flow from Schedule 1 to line 10, and AGI appears on line 11.
How it differs from related terms
- Gross income: income before the adjustments used to reach AGI.
- Taxable income: generally the amount remaining after the standard or itemized deduction and other applicable deductions are taken from AGI.
- Modified adjusted gross income (MAGI): a program-specific calculation that starts with AGI and adds back specified items. There is no single MAGI formula for every tax benefit.
Where AGI is used
AGI can affect eligibility or limits for deductions, credits, filing services, and other tax rules. Some non-tax procedures also use prior-return AGI. For example, the alternative Form 15227 route for a first IRS IP PIN applies its own current AGI thresholds, which must be checked on the current form.
Finding prior-year AGI
Use the filed return, IRS Online Account, or a free IRS tax return transcript for the relevant year. Do not use a refund amount, tax owed, or current-year estimate as a substitute.
Example
If total income is $50,000 and eligible adjustments to income total $2,000, AGI is $48,000. This simplified example does not decide which income or adjustments apply to an individual return.