What’s on the BCBA Exam? 6th Edition Content Areas (2026)
As of September 2026, the BCBA exam covers 9 content domains defined by the BACB’s 6th Edition Test Content Outline, the version in effect for every administration per the BCBA Handbook (updated June 2026). The exam itself is 185 multiple-choice questions: 175 scored plus 10 unscored pilot items you cannot distinguish from the scored ones, delivered in a single 4-hour appointment at an authorized Pearson VUE testing center. Domain weights range from a low of 5% (Behaviorism and Philosophical Foundations, 8 questions) to a high of 14%, a weight shared by two domains: Concepts and Principles (24 questions) and Behavior-Change Procedures (25 questions). Three domains sit in the low teens: Measurement, Data Display, and Interpretation at 12% (21 questions), and Ethical and Professional Issues and Behavior Assessment tied at 13% each (22 and 23 questions). Selecting and Implementing Interventions and Personnel Supervision and Management each carry 11% (20 and 19 questions), and the two smallest domains are Experimental Design at 7% (13 questions) and Behaviorism and Philosophical Foundations at 5% (8 questions). Here is the full domain by domain breakdown, plus a sample question.
Figures from the BACB’s 6th Edition Test Content Outline and the BCBA Handbook, updated June 2026, checked September 2026.
The 9 BCBA Content Domains, Ranked by Weight
Every question on the BCBA exam maps to one of these 9 domains. The bars below show each domain’s share of the 175 scored questions, scaled so the largest domains reach roughly 90% width.
What Each Domain Actually Covers
Concepts and Principles (B) is the vocabulary the rest of the exam is built on: reinforcement, punishment, extinction, motivating operations, and stimulus control. Behavior-Change Procedures (G) tests the techniques that follow from those principles, from differential reinforcement to prompting, chaining, and shaping. Together B and G make up 28% of the scored exam, 49 of the 175 questions, making them the single largest block of content by a wide margin.
Ethical and Professional Issues (E) applies the BACB’s ethics principles to practice scenarios rather than testing rote recall of a code. Behavior Assessment (F) covers how a behavior analyst identifies what is maintaining a behavior, from indirect interviews through descriptive data collection to functional analysis. Measurement, Data Display, and Interpretation (C) tests how behavior is recorded, graphed, and read for trend, level, and variability. Selecting and Implementing Interventions (H) and Personnel Supervision and Management (I) sit close together in weight: H covers choosing and applying a treatment plan responsibly, while I covers supervising RBTs, trainees, and other staff. Experimental Design (D), at 7%, focuses on single-subject designs and what makes a demonstration of a functional relation credible. Behaviorism and Philosophical Foundations (A) is the smallest domain at 5%, covering the conceptual base the field is built on, such as why behavior analysts favor environmental explanations over mentalistic ones.
Why Domain Weight Should Drive Your Study Plan
A study plan that spends equal time on all 9 domains misallocates effort, since Concepts and Principles and Behavior-Change Procedures together carry twice the weight of Ethical and Professional Issues or Behavior Assessment individually, and four times the weight of Experimental Design alone. That does not mean skipping the smaller domains. Experimental Design is only 7% of the exam, but a candidate who cannot distinguish a reversal design from a multiple baseline design will still lose points there every attempt, since every scored question counts the same regardless of which domain it falls under. The practical takeaway is proportional coverage: budget study time roughly in line with the weights above, and treat every domain, even the smallest, as fair game rather than optional.
It also helps to notice which domains tend to overlap in practice. Concepts and Principles (B) supplies the terminology that Behavior-Change Procedures (G) and Behavior Assessment (F) both apply, so weak footing in B tends to cost points in more than one domain at once. Measurement (C) and Experimental Design (D) are similarly linked: reading a graph correctly (C) is part of how a behavior analyst evaluates whether a single-subject design (D) actually demonstrated what it was meant to. Studying these pairs together, rather than working through the 9 domains strictly in isolation, mirrors how the exam actually tests the material.
Ready to see how you score across all 9 domains? Try our BCBA practice test, or start with a free BCBA practice test to check your baseline before you build a study plan.
Frequently Asked Questions
How many questions are on the BCBA exam?
185 total: 175 scored questions plus 10 unscored pilot questions mixed in randomly, so you cannot tell which items are pilot items during the exam. All 185 are answered within a single 4-hour appointment.
What are the 9 BCBA content domains?
Behaviorism and Philosophical Foundations, Concepts and Principles, Measurement Data Display and Interpretation, Experimental Design, Ethical and Professional Issues, Behavior Assessment, Behavior-Change Procedures, Selecting and Implementing Interventions, and Personnel Supervision and Management, as defined by the BACB’s 6th Edition Test Content Outline.
Which domain carries the most weight on the BCBA exam?
Concepts and Principles and Behavior-Change Procedures are tied for the highest weight at 14% each, 24 and 25 questions respectively, of the 175 scored questions.
Is the BCBA exam still based on the 6th Edition Test Content Outline as of 2026?
Yes. Per the BACB’s test content outline index page, checked September 2026, the 6th Edition remains the only current BCBA outline, with no successor edition or transition date listed.
Sources
- Behavior Analyst Certification Board, BCBA Test Content Outline (6th ed.)
- Behavior Analyst Certification Board, Test Content Outlines
- Behavior Analyst Certification Board, Examination Information
- bacb.com, BCBA Handbook (updated June 2026)
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