tax calculation

How can we file ITR-2 through offline utilities.

should I pay 15% on total income Rs. 27,800/- from STC Gain?

or

Need to pay 15% on   2,48,000 + 27,800 = 2,75,800 - 2,50,000 (Basic Exemption)

                                                                   =25,800 * 15%

                                              Tax Payable =3,870 /-

which is the correct way?? Kindly help me.....

Dear Sir,

https://www.incometaxindia.gov.in/pages/tools/income-tax-calculator.aspx

But I calcuted my tax on above link (Income tax calculator available on Income tax India's website).

it's showing -

Short Term Capital Gains (Covered u/s 111A) 15%  = 25,800 * 15%

                                                                                  = 3,870 - 2,500 (relief u/s 87A)

                                                                                  = 1,370 + 41 (Education Cess + Secondary and higher education cess)

                                                                                  = 1,411 (Net Tax Payable)

Kindly clear this confusion !!!!!!!!!!!