Underglow in California
Underglow is legal in California, including while driving, if diffused and dim (≤0.05 cd/sq in, ≤720 sq in total), not red toward the front, and not flashing.
Verified against primary sources · August 2026
What the law says
CVC 25400 permits diffused neon/LED accent lighting while driving within brightness (0.05 candela/sq in) and area (720 sq in) caps, kept 12+ inches from required lamps. Red visible from the front is prohibited (CVC 25950), as is any flashing light.
Specific Limits
- Banned
- red visible from front; flashing; within 12 in of required lamps
- While driving
- allowed
- Max brightness
- 0.05 candela/sq in
- Max total area
- 720 sq in
Frequently Asked Questions
Are underglow legal in California?
What are the exact underglow limits in California?
Street-legal underglow picks
Gear that helps you mod without a ticket in California.
The glow that's legal in every state — inside the cabin instead of under it.
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