TIRES - Which is the bigger size?

Ok.. So I have spent a quite a few hours trying to figure out tire sizes, metrics, math.. I even broke out the test tubes and still couldn't figure it out.

Which of these is the biggest tire that will fit on my Tacoma? I don't understand the difference between the two options I boxed up in red

Stock 1999 Tacoma SR5 V6 4WD.



I have 15in wheels on there now, and I am going to tour Death Valley and chase some motorcycles as we are shooting a motorcycles series for National Geographic. I can pick the tires out, I just need to find the biggest tire size that will fit on my stock Taco.

 

http://www.redrock4x4.com/tireconversioncalculator.html

 

they are both the same size. My last set of tires on my '99 tacoma was a pair of 31 x 10.5 x 15's .

 

Thank you all very much! Now gotta send the link to the boss and let him buy them for me

 

Technically, a 31/1050r15 is a bigger tire than a 265/75r15. (But only by a fraction of an inch).

One thing to keep in mind is that you've got a much wider selection of tires to choose from if you go with the 31s instead of 265s.