CSLB Electrical (C-10)
Free practice for the California CSLB C-10 Electrical trade exam — the craft/classification test you take in addition to the Law & Business exam. Original questions in English, 中文 and Español, with 2023 NEC / 2025 California Electrical Code references.
To get a C-10 Electrical license you must pass BOTH exams — the Law & Business exam and this C-10 Electrical trade exam. Both are about 3.5 hours at a PSI center. CSLB does not publish the exact question count or passing score for the trade exam; you're told the passing mark at the test site.
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🎯 Full timed mock exam
A 100-question, 3.5-hour simulation to test your readiness.
What the C-10 trade exam covers
24%
Branch Circuits & Wiring
branch circuits · GFCI/AFCI · raceways · box & conduit fill · ampacity · voltage drop
22%
Services & Distribution
services · feeders · load calcs · grounding & bonding · OCPD · transformers
22%
Equipment & Systems
motors · HVAC · lighting · generators · solar · pools · low-voltage
12%
Planning & Estimating
plan & one-line reading · load-calc methods · permits · estimating
12%
Safety
Cal/OSHA · lockout/tagout · arc-flash PPE · working space · trenching
8%
Testing & Troubleshooting
meters · Ohm's law · fault diagnosis · grounding checks · terminations