If you are using TurboTax Online, you can preview your form 1040 by following these steps:
You can view your Form 1040 plus Schedules 1, 2 and 3 at any time using the online editions. Click on Tax Tools on the left side of the online program screen. Click on Tools. Click on View Tax Summary. Click on Preview my 1040 on the left side of the screen.
If you are using TurboTax Online, you can preview your form 1040 by following these steps: