How do I see my Modified Adjusted Gross Income on my current (2021) tax form that has not yet been filed?

1 option is to enter the data and see the results.

Another, or supplemental option is to view the forms turbotax generates:

Click the "Forms" icon in the blue bar at the top right of your screen.
From the list of forms, click the form you want to review.
Review as many forms as needed.
Hint: You can also review your state(s) forms here.
To return to the step-by-step process, click the "step-by-step" which is in the blue bar at the top right of your screen, where the "Forms" icon formerly was located.

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Modified AGI is not listed anywhere on the 1040.

You start with your AGI (1040 line 11) and adjust (if necessary) from there.

Add up your gross income from all sources.
Check the list of “adjustments” to your gross income and subtract those for which you qualify from your gross income. The list is on the 1040 form under Schedule 1.
The resulting number is your AGI.
Add back any deductions for which you qualify; these can include student loan interest and individual retirement account contributions.
The resulting number is your MAGI.

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