When entering dollar amounts on a W-2 or 1099, do I put the exact amount with dollars and cents? or round up or down to nearest whole dollar?

Enter the exact amount.  TT will do the rounding correctly.

Thank you for the quick reply.   I have already entered multiple 1099s and W-2s and properly rounded up and down to the nearest whole dollar.  Would I need to go back and adjust all number to exact numbers, or just leave them as is?  And then in the future I will just enter the exact numbers and let TurboTax round for me.

looking at my own IRS transcript I noticed that IRS always rounds down.

Either way.  If you enter  the exact amount then Turbo Tax will round them.