my fuel gauge reads empty at times when I know it is between half and full

usually when this happens,and it happens on most years,makes and models,toyota,chevy,ford,bmw,mercedes,gm,and more.it's the fuel gauge sending unit.it seems that it is only available at the dealer.i have a part number. 83320-34041 FUEL GAUGE SENDING UNIT SEQUOIA.you are still driving it,so the fuel pump is still working.they are both located in the fuel tank.you can continue to drive it,if you can't fix or have it fixed right now.if you know how many miles you get per tank full,say 400 miles.just go fill it up and set the odometer trip button to ZERO,and when you put say around 350 miles on it,fill it up,reset trip button and drive on.or when you are ready to fix it,you can just replace the sender only,or the sender and the pump.either way the tank has to be removed to do this.toyota fuel pumps last longer than most vehicles do.