What-if scenarios
Try a bigger expense or a different income for the year and see how your tax estimate and quarterly payments would change. Nothing is saved.
Try an extra expense
Under What-If Scenarios on the Taxes page, tap an expense, such as +$5K Equipment or +$2K Software, or choose Custom and enter your own amount. Tap more than one to add them up.
Potential savings shows how much less tax you would owe. The quarterly payments show What-if applied while a scenario is on. Tap the expense again to take it off. Nothing changes in your books, and marking a quarter paid always uses your real estimate.
Try a different income
Choose Project a different income, then Open, on the Taxes page (on a phone browser, What-If Scenarios). Drag Project Your Income to raise or lower your full-year profit. Estimated Tax shows the new total and how it compares with your current estimate, and Adjusted Quarterly Payments shows what each payment would be.
Projecting a different income is on Co-Pilot and Command. Trying extra expenses on the Taxes page is on every plan.
In the phone app
Open the Taxes tab and choose What-If Scenarios. It works the same way as on the web.