calculation between multiple textbox

Question

   Total Tax Amt    Waive Amt     To be paid TaxAmt Current Year Amt       Previous Year Amt       Interest Amt       Penalty Amt       Total Amt


hi,,i have one table as given above,,,,there are textboxes in each field,,i want to perform calculation between all textboxes with the use of javascript,,how can i do that?plz provide me code..thank you