self-emploment tax calculation

What exactly do you want to change, and why? The calculation of the tax is automatic and you don't have any choice about how it's calculated. The calculations are done according to the tax laws.

Or do you mean that you want to change some information that you entered? If so, have you already filed your tax return or are you still working on it?

@Revrich71 - This computation is based on the net income from self employment.

The only guaranteed way to adjust your self-employment tax is to increase or decrease your business-related expenses. This will adjust your net income and correspondingly change your self-employment tax. Regular deductions such as the standard deduction or itemized deductions won't reduce your self-employment tax.