CID Study Guide 2026
Everything you need to pass the CID exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
CID exam key facts
- The IDEX California exam includes 150 multiple-choice questions. Source
- Candidates have 3 hours to complete the IDEX California exam. Source
- The IDEX California passing score is not a fixed percentage but is set in advance using a modified Angoff method. Source
- Candidates retaking the IDEX California exam must pay their re-testing fees before the registration deadline. Source
- A California Certified Interior Designer certification expires 24 months after its issue date. Source
📋 CID Exam Format at a Glance
📚 CID Topics to Study (45)
✍️ Sample CID Questions & Answers
1. In the 60-30-10 rule of color distribution, the 10 percent typically represents what?
In the 60-30-10 rule, 10 percent is reserved for the accent color.
2. Which color rendering index (CRI) value is considered the minimum acceptable for spaces requiring accurate color perception, such as retail showrooms?
A CRI of 80 or above is considered the minimum acceptable threshold for spaces where accurate color rendering is important.
3. With regard to sole traders, drawings are not an allowable expense.
For sole traders, 'drawings' refer to money or assets taken out of the business by the owner for personal use. These are considered a reduction in the owner's capital, not an expense incurred by the business to generate revenue. Therefore, drawings are not an allowable expense for tax purposes and cannot be deducted from business profits.
4. Placing a bright yellow chair in an otherwise neutral gray room primarily uses which principle to draw attention?
Strong difference in color creates contrast that pulls the eye to the chair.
5. What is bilateral symmetry?
Bilateral symmetry is a specific type of symmetrical balance where a composition can be divided by a central axis, and both sides are essentially mirror images. While the definition provided mentions 'slight variation,' in its purest form, bilateral symmetry implies near-perfect mirroring. It's a fundamental concept in biology and art, creating a sense of order and recognition.
6. Which flooring material is naturally antimicrobial and made from renewable cork oak bark?
Cork is harvested from bark, is renewable, and has antimicrobial properties.
🎯 Free CID Practice Tests
📖 CID Guides & Articles
What Practice Test Geeks adds beyond an AI chat for CID
An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:
- A timed, full-length CID mock exam — 150 questions in 180 minutes with a 70% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
- A fixed CID question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
- Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
- A printable CID cheat sheet you can print or save as a PDF.
- CID flashcards built from the same question bank.
- Free CID practice tests with the correct answer shown after each question.
How this page was made: written with AI tools and published by Nathan Beja, founder of Practice Test Geeks, who is responsible for its content. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy
Sources & references
Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy
- ccidc.org — Fees, registration deadline, retake fee, retake policy, test dates, renewal, score validity, eligibility, exam format, passing score · verified Oct 2026