Wheel offset

Hi all,
Looking to put some new wheels and tires on my truck.
Right now I have 285 55 20’s on TSS bbs wheels. They’re 20x9 and as I understand it, have an offset of +50.

I’m looking at 20x9 KMC 535 Renegades in flat black.
They have an +18 offset.
I’m thinking of putting 295 55 20’s on the wheels. Any comments on how far out they’ll be? Cheers

 

Offset is based on the center of the wheel width. A + offset is closer to the outside (visible) side of the wheel. A negative is closer to the inside.

A +50 offset means the wheel moves IN to the vehicle 50mm. So a +18mm offset will only be 18mm in.

The new wheels will stick out 38mm(1.25inches) more than the current wheels.

EDIT: YOU NEED TO CONSIDER WHEEL WIDTH. If you change wheel width. You have to subtract (or add) half the difference.

For example: a 9" wheel with a +50 offset to a +18 will give you 1.25" further out.. But a 9" at +50 to an 8" at +18 will only give you 0.75" further out. It's all relative to wheel width.
Visual reference:

 

That sounds great, thanks!

 

This is +12 offset

 

You don’t need to calculate all that. And wheel width doesn’t make a difference because the tire width will determine the final poke. Use this formula for exact poke. It’s pretty ingenious.
https://www.tundras.com/posts/189124

 

That’s awesome, thanks.

295/2 - 18 - 90
=39.5
1-1/2” total

cheers