What does the 12000 deduction mean

[DoninGA]

The Standard Deduction when filing as Single is $12,000.

[koreycooksey]

what do you get back on a refund?

[VolvoGirl]

You don’t get that back.  The Standard Deduction is subtracted from your income before the tax is calculated so you get taxed on a lower amount.  It means the first 12,000 of your income is tax free.

[VolvoGirl · Accepted solution]

You get to deduct either the Standard Deduction or your Itemized Deductions whichever is more from your income.  Everyone gets a Standard Deduction.  That means for Single the first 12,000 of income is not taxed (or tax free).  

This year the Standard Deduction will be doubling so many people will be switching to the Standard Deduction.  And there is a max 10,000 limit (5,000 MFS) of property tax and state taxes "SALT".

FAQ on 2018 changes https://ttlc.intuit.com/questions/4482394-how-will-tax-reform-affect-my-2018-federal-tax-return

For 2018 the standard deduction amounts are:
Single 12,000 + 1,600 for 65 and over or blind
HOH 18,000 + 1,600 for 65 and over or blind
Joint 24,000+ 1,300 for each 65 and over or blind
Married filing Separate 12,000 + 1,300 for 65 and over or blind