Metric size for front axle nut!

I have been trying to find the size of the front axle nut . It is not the same size as the rear. And I don't seem to be able to size it in the repair manual. None of my existing sockets seem to be the right fit and I want to avoid rounding the corners . I picked up the socket for the rear yesterday and at that point thought it would be the same as the front. I have metric sockets up to 20mm so it has to be somewhere between 20 and 27  I am guessing possibly 23 or 24 ?  Does anyone on the forum have a definitive answer. I am hoping to remove the wheels this afternoon so the tires can be replaced early next week . 

Happy Father's Day to all the Dad,s out  there in ether space.

Cheers,
Scroller

22mm  I also did a bump on tire removal/installation. That search function comes in handy.

Thanks for the quick response I will have to try and scrounge one up today . I have been looking at the pictures on the site and they should help a great deal. 

Cheers,
Scroller.