The standard deduction for Married Filing Joint with both over 65 should be:
$24,800
In addition if both of you are over 65 (see below) then you would qualify for an additional $1,300 each or $2,600 total.
You must turn 65 by the last day of the tax year to qualify for this additional deduction, but the IRS says you actually turn 65 on the day before your birthday. That means you would qualify on December 31 if you were born on January 1—just in the nick of time to claim the extra deduction for that tax year.