Study plan
How to Pass the Salesforce Certified JavaScript Developer I Exam
A study plan for the Salesforce Certified JavaScript Developer I certification exam, built from the official domain weights instead of a generic template. Focus heavily on the nuances of the 'this' keyword, prototypical inheritance, and the mechanics of Promises. Practice hands-on DOM manipulation and array transformations using modern ES6 syntax rather than legacy methods.
- 7 domains
- 60 questions
- 105 min
- 65% to pass
certilumStudy in weight order, not topic order
The plan below follows the official blueprint weights, so the order of study is the order that returns the most points.
- 1
Objects, Functions, and Classes
25%- Arrow functions vs regular functions
- Object destructuring
- Prototypes and Prototypal inheritance
- Class syntax and constructors
- +1 more topics in the blueprint
15 practice questions tagged to this domain.
- 2
Variables, Types, and Collections
23%- let, const, and var scope
- Primitive vs Reference types
- Template literals
- Array methods (map, filter, reduce)
- +1 more topics in the blueprint
14 practice questions tagged to this domain.
- 3
Browsers and Events
17%- DOM manipulation
- Event bubbling and capturing
- Event delegation
- Web APIs
- +1 more topics in the blueprint
10 practice questions tagged to this domain.
- 4
Asynchronous Programming
13%- Promises
- Async/Await
- Event Loop
- Microtasks vs Macrotasks
- +1 more topics in the blueprint
8 practice questions tagged to this domain.
- 5
Server-side JavaScript
8%- Node.js basics
- Module systems (ESM vs CommonJS)
- Process environment
5 practice questions tagged to this domain.
- 6
Testing
7%- Unit testing fundamentals
- Test runners
- Assertion libraries
4 practice questions tagged to this domain.
- 7
Debugging and Error Handling
7%- Try/Catch blocks
- Error types
- Debugging tools in browser
- Stack traces
4 practice questions tagged to this domain.
Three phases, in order
Most failures are process failures, not knowledge failures.
Phase 1 — Learn the high-weight domains
Start where the points are. The first domains on this plan carry the most weight, so a gap there costs the most. Cover the objectives, then close each topic with practice questions you actually get wrong.
Phase 2 — Close the mid-weight domains
The middle of the blueprint is where most candidates plateau. These domains are worth less per topic than the first phase, but they add up fast, and they are the usual difference between a near miss and a clear pass.
Phase 3 — Timed full mocks
Stop reading new material at this point. Run full-length exams under the real time limit and the real format, and use the per-domain breakdown to find which domain is still costing you the pass.
Where we put the emphasis
Validating core language proficiency to ensure developers can build robust components for the Lightning Platform.
The order matters less than the loop. Every domain you finish should end with questions you got wrong, because the mistake is the only thing you actually needed to study. On the Salesforce Certified JavaScript Developer I that loop is worth 7% of the exam in the first block alone.
More about the Salesforce Certified JavaScript Developer I exam
Explore the rest of this page series: format, cost, difficulty, requirements and how to prepare.
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Frequently asked questions
Everything you need to know about the Salesforce Certified JavaScript Developer I exam.