I’m currently working on version 2 of the Tyre Size Calculator, it’ll fix some inconsistencies in the current version and add a few new features that commentors have asked for e.g.
- Bike Tyres
- Mud Tyres
I’m also thinking of adding the option to specify the wheel width so you can see how fat or stretched the selected tyre size will be on a given wheel width.
If anybody has any comments of suggestions then feel free to post them below 
So… any progress in version 2 ??
I would like to be able to change MPH to KPH.
Impact of the tyre size change. Interms of high speed impact details etc..
Specially adv and disadvantages.
- metric / imperial sizes both shown. (ie so we know as 235/85 16 is nearly 32″)
- switchale end view (to show comparative width).
- over/under speeds shown in imperial and metric.
Here’s a couple of things to add:
- High Flotation Tires
- Tire Width to Rim Width ratio with a “Acceptable”/”Warning” note
- What is the IDEAL tire to rim width?
- Rim offset calculator (to allow you to go from one width to another while minimizing the risk of damage to the wheel bearings)
Too narrow of a section width to rim width ratio becomes VERY dangerous due to the fact that the tire bead can come free of the rim easier. In addition, it can also cause the outer sections to press against the road and the center to lift up creating an unusual treadwear pattern. However, I know you can usually get away with wider tires than rims. But, how wide is too wide? I’ve seen people run very wide tires for their rims and not have problems. But, I also have seen some tires that just wear funny because of how they’re made. Too wide of a tire causes the tread pattern to baloon out causing uneven treadwear and certain handling issues.
Currently, I run P255/70R15 on my 15x7J factory rims. According to research I’ve done, the manufacturer provided multiple sizes for my Jeep. They were 215/75R15, 225/70R16, 225/75R15, 235/75R15, and 245/70R15. My door tag says 225/70R15 mounted on 15x7J rims.
Interesting. isn’t it?
Cheers
Hi Insomniac. I’ve been trying to find a tyre size calculator that includes rim-width in it’s inputs – this can have a considerable effect on sidewall height, i.e. a 205/45 tyre on a 8″ rim will be seriously stretched, but will be baloon-like on a 6″ rim.
If you can work out how to incorporate this (preferably along with a cross-sectional view) I can guarantee you’ll get loads of hits just from the euro-look brigade, let alone the ricers, pro-tourers etc
It would be nice to have revolutions per mile/km, speed difference (obviously only if speedo is correct) Maybe even RPM at given speed
Maybe…..
I’ll include those stats in the next version for you
For those of us wanting to size a suitable space saver wheel, it would be good to have the calculator work down to the 115 and possibly below width ranges.
a 3d effect to see all the angles of the tire
give me please code of calculator for my site
Hi Sergey,
Unfortunately I do not give out the code for my utility. The calculator generates most of the money to pay for my hosting at the moment so I don’t want to reduce that by handing the code out.
I’ll email you at the address you provided about a branded version tho.
taste isnt factory standart equipment….
Hi insomniac, do you mind If I have a link to this calculator? perhaps at some stage you would link back to me?
Any chance of getting a conversion rate for tyres that are labelled 31 x 10.5 x 15 or similar, so going from 235/75 R15 to 30 x 9.50 x15 could possibly be helpfull or indeed many many other sizes.
Hi Ken,
It shouldn’t be a problem to add in the option for these notations. Its mainly 4×4, mud tyres and light trucks isn’t it?
I would like to suggested you to enable us to fit or select the rim type as well. So, we may select the best rim that nice to be fit to our vehicles and know what best behind it with your powerful calculus..
You may link it with rim manufacturer or supplier. At the same time U might be their sole distributor or agent thru web or online! Seem cousin of e-bay…..cheese !
Hi Nicerule,
Thats a good idea, ambitious… but good. I’ve already had a few companies interested in using my calculator but so far I’ve declined, the amount of time I have to spend on these little projects is decreasing quickly as I’m soon to be a father so right now I’m hoping I can just get V2 finished before then!
PS, do you run paultan.org? Its an excellent site
Hi there, is there any chance of getting a copy of this calculator? It is the BEST thing I have seen on the web to help me with working out stuff but unfortunately I am pretty far off the road and dont have internet. Any chance of being able to get it ?
Hi netminder,
This is the first time I’ve checked my blog in at least a month. My daughter was born three weeks ago, 4 weeks early so I’ve been super busy elsewhere.
I’ve a couple of completely unrelated iPhone apps in the pipe that are only about 10% finished. Once I’ve finished them and I’m comfortable with the submission process I’ll definately think about doing the tyre calc as an app. Dunno if it’d be worth 59p/99c tho.
Maybe you should develop it as an iPhone app, and sell it on the Apple App Store. That way you can still make a few bucks, and keep us tyre nuts happy.
That would be grand! Really appreciate it if you are able to let the old one out when the new one comes in
It’s a really top notch little program!!
Hi Jimmy. I’ve been emailed a few times about this but I’m reluctant to release a flash executable as the calculator accounts for about 80% of my sites overall traffic and at the moment the resulting ad revenue is paying for my hosting. I’ll keep your request in mind and may release a cut-down version of the old calculator once the new one is ready
a nice bit to add would be… I know what my “Factory” wheel and tire sizes are, if I want to increase the radius of the wheel, what size tire would I need to keep the same rolling radius as my current stock set up.
Thats a great idea Tony. I’ll add that one to the list and get working on it. Thanks
I’d like to be able to change from mph to kph, and also change the speeds like at 10kph, 15kph, 40kph or 100kph. I also like your ides of seeing how sterched a tire will be. that would be good.
I’ll definately include a switch for mph/kph, maybe even a cm/mm/inch switch?