is there a way to see the calculation of line 16 "tax" on form 1040?

[VolvoGirl]

Even though the full amount shows up in the total income on the 1040 lines 3b or 7, if you have capital gains or qualified dividends the tax is not taken from the tax table but is calculated separately from Schedule D. The tax will be calculated on the Qualified Dividends and Capital Gain Tax Worksheet. It does not get filed with your return. In the online version you need to save your return as a pdf file and include all the worksheets to see it.

Save the PDF
https://ttlc.intuit.com/community/saving/help/how-do-i-save-my-turbotax-online-return-as-a-pdf/00/26...

For the Desktop version you can switch to Forms Mode and open the worksheet to see it. Click Forms in the upper right (upper left for Mac) and look through the list and open the Qualified Dividends and Capital Gain Tax Worksheet. And you will need the IRS Tax Tables

IRS Qualified Dividends and Capital Gain Tax Worksheet—Line 16 on 1040 instructions page 36. And you will need the IRS Tax Tables starting on page 64 or the Tax Computation Worksheet on page 76.

https://www.irs.gov/pub/irs-pdf/i1040gi.pdf

[rjs]

There are 7 different methods that can be used to calculate the tax on Form 1040 line 16, depending on what types of income you have and other things in your tax return. VolvoGirl explained one of the 7 methods above.

The conditions for determining which of the 7 methods to use are explained on page 36 of the DRAFT 2025 IRS Instructions for Form 1040. (The IRS has not yet published the final instructions for 2025.)

If you are using the desktop TurboTax software you can see which method TurboTax used by looking at the 7 checkboxes in the Tax Smart Worksheet in forms mode. The Tax Smart Worksheet is between lines 15 and 16 in the first section of the "Form 1040 or Form 1040-SR Worksheet."

[mesquitebean]

Adding on to @ rjs comment above about desktop software, there is also a way in Online TurboTax to see what tax calculation method(s) were used.  It's similar, but the navigation is different.  Note: for Online users, this only works for the current year return.

• With your online return interview open, go to the left column menu and choose the tab TAX TOOLS, then the subtab TOOLS.
• On the Tools screen choose VIEW TAX SUMMARY.
• On the Tax Summary screen go to the left menu column and select PREVIEW MY 1040.
• When the 1040 displays, scroll down to the space between Lines 15 and 16, where you should see a TAX SMART WORKSHEET, which should show the calculations methods that TurboTax is using.