imperial to metric tyre sizes ??

i have some 15" wheels fur me classic i bought dirt cheap some time ago that have metric tyres on em, (30 x 9.5 x 15) two are brand new and 2 are fkd. i now know why they were cheap coz i'm really strugglin to get another pair in that size:drama: somebody told me that i could put insa turbo dakars on in 235/75/15 and they will be the same diameter, problem is i am a bit :der: at maths and can't figure out if they will be ok
is there anyone cleverer who can help

lookie here

go all the way down to the "light truck imperial tyre sizes" bit, theres a convertor at the bottom of the section, strange enough your size was already up

it says the equivilent is 240/80/15

also says same here

interesting to know too, khumo enduro's AT's 31/10.5/15 are equivilent to 265/75/15, which should go on if you had the clearance in ure arches

heres a q? whats the size across? 8"?

thanks metallica that's really handy
the middle number on the imperial tyres is the tread width so i should imagine 10.5 inches would be too wide?
i put a few sizes thru the oz site and it works out that a 235/85/15 should work out only a few mm different to my metric ones not the 235/75/15 i was told but i dunno if i can get em i'll have to have another look around

well yeh tread width, i meant width of the wheel

no worries, best bet find someone who sells metric tyre sizes in 15" wheel and go from there i suppose, if a company dont have them in your size, ask them if they can get them

sorry my fault :der:
i can't remember what width the rims are, they're miles away in me workshop so can't check til monday
after lookin about you are probably right and the 31/10.5's are probably my best bet, only thing is i was hoping to just buy a pair as the 2 9.5's i have are new but there doesn't seem to be anything close to them in metric. i did find out that insa make the imperial size i want in the sahara tread pattern but i guess they don't have any in the country as the guy i spoke to offered me the 235's as nearest available and said there were only 5 in the uk til feb

my head woz hurtin from doing the maths and i managed to find a pair of cooper tyres in the 30/9.5/15 i was lookin for after ringing a few distrubuters got no idea what they're like but at least it saved me having to buy 4 tyres for now