As large language models (LLMs) continue evolving, developers are increasingly turning to them to assist with complex coding tasks, including building JavaScript apps from scratch. Whether you’re building a simple Todo App in React or an interactive Snake Game in Three.js, choosing the right LLM can make a significant difference in code quality, performance, and ease of use.
Why Use LLMs for JavaScript Development?
JavaScript is the most widely used programming language today, powering both front-end and back-end applications. LLMs trained on vast codebases can:
Autogenerate boilerplate code
Refactor and debug complex logic
Explain errors and suggest improvements
Speed up the learning process for frameworks like React and Three.js
But which LLM actually performs best in hands-on coding scenarios?
Example 1: React Todo App
Objective: Build a functional Todo app using React, with features like state management, adding/removing tasks, and data persistence (e.g., localStorage).
What We Tested:
JSX generation accuracy
React hooks usage (e.g.,
useState
,useEffect
)Component modularization
LocalStorage integration
Real-time code correction
Example 2: Snake Game Using Three.js
Objective: Create an interactive 3D Snake Game using Three.js with basic controls, collision detection, and scoring.
What We Tested:
Scene setup with
THREE.Scene()
Mesh manipulation
Game loop logic using
requestAnimationFrame
Keyboard control handling
Code readability and frame rate optimization
GPT-4o (OpenAI): The Most Reliable for Full-Stack JS
GPT-4o is OpenAI’s latest multimodal model, and it’s an absolute powerhouse for developers. It excels at both frontend and backend JavaScript workflows.
Key Strengths:
Perfect handling of React lifecycle and hook logic
Accurate Three.js rendering suggestions
Smooth debugging and async logic handling
Super responsive in multi-turn conversations
Verdict: Best all-around LLM for JavaScript development. Great for full-stack apps and game logic.
Claude 3.5 (Anthropic): Human-Like Code Reasoning
Claude 3.5 Sonnet brings near-human reasoning to code, especially strong in maintaining coding style and structure.
Key Strengths:
Clean, modular code output
Excellent at breaking down component logic
Intuitive React explanations
Slightly weaker on 3D logic with Three.js but improving
Verdict: Best for clean, readable React codebases. Not ideal for 3D-heavy tasks.
Gemini 1.5 Pro (Google): Best for Collaborative Coding
Gemini 1.5 Pro integrates beautifully with Google’s ecosystem and supports long-context coding with strong JavaScript comprehension.
Key Strengths:
Long context handling—great for large projects
Strong React documentation support
Solid with vector-based graphics in Three.js
Verdict: Ideal for larger codebases and team collaboration, though its 3D logic is slightly behind GPT-4o.
DeepSeek R3: Fast but Inconsistent
DeepSeek R3 is a lean, code-specialized model that offers fast performance but lacks some of the nuance in complex JavaScript tasks.
Key Strengths:
Quick at boilerplate code
Handles basic React apps decently
Struggles with complex 3D logic or async operations
Verdict: Decent for junior developers or boilerplate React work, not ideal for advanced game logic.
Grok (xAI): Needs Work for JavaScript
xAI’s Grok is Elon Musk’s answer to LLMs, optimized for humor, creativity, and brevity. While Grok is promising in conversations, it’s still catching up in software development tasks.
Key Strengths:
Basic JavaScript output
Passable for simple UI logic
Weak Three.js support and sparse debugging insights
Verdict: Fun for creative prompts, not reliable for serious JavaScript development yet.
Which LLM Should You Use?
GPT-4o: The All-Around Performer
GPT-4o represents OpenAI’s most advanced multimodal model, offering exceptional capabilities for JavaScript developers working with React and Three.js.
Strengths:
- Superior code generation quality across both React component architecture and Three.js scene setup
- Excellent understanding of 3D mathematics and shader programming
- Strong ability to debug complex rendering issues and performance bottlenecks
- Comprehensive knowledge of modern JavaScript frameworks and libraries
- Multimodal capabilities allow for analyzing screenshots, diagrams, and visual references
Best for:
- Complex Three.js implementations requiring custom shaders
- React applications with sophisticated state management
- Projects requiring both UI development and 3D visualization
- Developers who need reliable, production-ready code suggestions
Limitations:
- Higher API costs compared to alternatives
- May generate overly complex solutions for simple problems
Claude 3.5: The Frontend Specialist
Claude 3.5 excels at producing clean, readable, and well-structured frontend code, making it particularly valuable for React developers.
Strengths:
- Exceptional at generating modular, maintainable React components
- Superior documentation within code comments
- Strong understanding of React best practices and patterns
- Excellent at explaining complex concepts in accessible language
- Produces highly readable code with consistent styling
Best for:
- Frontend-focused projects prioritizing code quality and maintainability
- Teams with varying experience levels who need well-documented code
- Projects requiring extensive component libraries
- Developers who value clean architecture and separation of concerns
Limitations:
- Less proficient with complex Three.js implementations
- May struggle with advanced WebGL concepts compared to GPT-4o
Gemini 1.5 Pro: The Collaboration Expert
Google’s Gemini 1.5 Pro offers unique advantages for team-based development and large-scale projects.
Strengths:
- Excellent integration with Google’s development ecosystem
- Superior handling of large codebases and project context
- Strong understanding of build systems and deployment workflows
- Good at generating code that follows established project patterns
- Effective at suggesting refactoring approaches for legacy code
Best for:
- Large teams working on collaborative projects
- Codebases requiring integration with Google Cloud services
- Projects with complex build and deployment requirements
- Developers working within Google’s ecosystem
Limitations:
- Less specialized knowledge of Three.js compared to GPT-4o
- May produce less elegant solutions for complex UI challenges
DeepSeek R3: The Rapid Prototyper
DeepSeek R3 offers a balance of speed and capability that makes it ideal for quick prototyping and learning.
Strengths:
- Faster response times than larger models
- Good understanding of fundamental JavaScript concepts
- Capable of generating functional code examples quickly
- Cost-effective for high-volume usage
- Suitable for educational purposes and skill development
Best for:
- Rapid prototyping and proof-of-concept work
- Developers learning JavaScript, React, or Three.js
- Projects with limited budget constraints
- Situations requiring quick iterations and feedback
Limitations:
- Less sophisticated understanding of advanced patterns
- May produce code requiring more manual refinement
- Not ideal for production-ready implementations
Grok: The Experimental Option
Grok represents an interesting but less mature option in the LLM landscape for JavaScript development.
Strengths:
- Novel approaches to problem-solving
- Can generate unconventional solutions
- Faster response times for simple queries
- May offer unique perspectives on coding challenges
Best for:
- Experimental projects and tinkering
- Generating alternative approaches to solved problems
- Developers interested in exploring different coding styles
- Non-critical applications where reliability is less important
Limitations:
- Less consistent code quality
- Limited understanding of complex JavaScript ecosystems
- May produce solutions that don’t follow best practices
- Not recommended for production environments
Decision Framework
When selecting an LLM for your JavaScript development needs, consider:
- Project complexity: More complex projects benefit from GPT-4o or Claude 3.5
- Team size and collaboration needs: Larger teams may prefer Gemini 1.5 Pro
- Budget constraints: DeepSeek R3 offers good value for limited budgets
- Learning vs. production: Learning environments can use simpler models like DeepSeek R3
- Specific technical requirements: Three.js projects benefit most from GPT-4o’s capabilities
The ideal approach may involve using different models at different stages of development, leveraging each for its particular strengths.
