SCCA® Solo / Autocross — unofficial classing tool
Know your class before the cones go up.
Pick your car, check off your mods, and see your class — plus exactly which modification bumped you and where you'd land without it.
Per-mod verdicts
Every tire, spring, and tune gets its own green or red flag — with the rulebook citation — so you know exactly which item moved you out of Street.
Deterministic, not vibes
Same build in, same class out, every time. Classification is computed by a tested rules engine over cited data — never guessed.
Share your build
Your whole configuration lives in the URL. Paste it in the group chat instead of typing your mod list for the fifth time.
How SCCA Solo classing works
Every car starts in a Street class (SS through HS) assigned by Appendix A of the Solo Rules. Modifications move it through categories: Street Touring for common bolt-ons — coilovers, intakes, wider 200-treadwear tires within per-class width limits — then Street Prepared for R-comps and deeper prep, and Street Modified for swaps and aero. One mod beyond a category's allowances moves the whole car. This tool resolves all of it deterministically, with the 2026 rulebook wording cited on every answer. Read the classing FAQ or browse 300+ verified cars.