How to read scale
1/8 means the model is one-eighth the size of the full vehicle. So 1/5 is the biggest ARRMA makes and 1/18 is among the smallest. As scale gets bigger (smaller denominator), the truck gets faster, heavier, needs more space and costs more to run.
Small scale - GROM (around 1/18)
The GROM line is ARRMA shrunk down. Small enough for a driveway, a park path or even a big indoor space, cheap to run on a small pack, and far less likely to hurt anyone. This is the pick for tight spaces or a young or first-time driver. Platforms like the Granite and Typhon come in GROM versions.
1/10 - the versatile everyday size
The 4X4 1/10 trucks - Senton, Vorteks, Big Rock and 3S Granite - are the friendly middle ground. Big enough to handle a real backyard and rough grass, small enough to be affordable and forgiving. A great first "proper" size.
1/8 - the basher standard
This is the classic 6S ARRMA size and where most serious bashers live. The Kraton 6S, Typhon 6S, Notorious and friends are big, fast and tough without being unmanageable. If you want the "real ARRMA experience" in one buy, 1/8 6S is it.
1/7 - the speed size
The Limitless and Infraction (and the 6S Mojave) sit at 1/7 - long, low and built for speed over open ground and pavement. Fast and dramatic, and they need room to run.
1/5 - the monsters
The 8S Kraton and Outcast are 1/5 scale - genuinely large, heavy machines that jump enormous and hit hard. Incredible to watch, expensive to feed, and they demand open space and experience. Not a first truck.
Which scale should you pick?
| Your situation | Best scale |
|---|---|
| Driveway / small yard / indoors | Small-scale GROM |
| Normal backyard, first proper truck | 1/10 4X4 |
| Want the full basher experience | 1/8 6S |
| Outright speed on open ground | 1/7 |
| Maximum size and drama, experienced | 1/5 8S |
Exact scale can vary by model year, so always check the specific listing - but this is the practical map of what each size is like to actually own.
Next: match a size to a power level with the 6S vs 8S guide, or see every model by platform.