Anthropic released Claude 3 with three models: Haiku, Sonnet, and Opus. They claim Opus beats GPT-4. I spent 30 days testing both in production.

Results: Claude 3 Opus wins on reasoning and code quality. GPT-4 wins on speed and cost. Here’s the detailed breakdown.

Table of Contents

Model Overview

Claude 3 Opus:

  • Context: 200K tokens
  • Cost: $15/1M input, $75/1M output
  • Strengths: Reasoning, code, analysis
  • Released: March 2024

GPT-4 Turbo:

  • Context: 128K tokens
  • Cost: $10/1M input, $30/1M output
  • Strengths: Speed, versatility
  • Released: November 2023

Setup

import anthropic
from openai import OpenAI

# Claude 3
claude_client = anthropic.Anthropic(api_key="your-claude-key")

def claude_completion(prompt, model="claude-3-opus-20240229"):
    message = claude_client.messages.create(
        model=model,
        max_tokens=4096,
        messages=[
            {"role": "user", "content": prompt}
        ]
    )
    return message.content[0].text

# GPT-4
openai_client = OpenAI(api_key="your-openai-key")

def gpt4_completion(prompt, model="gpt-4-turbo"):
    response = openai_client.chat.completions.create(
        model=model,
        messages=[
            {"role": "user", "content": prompt}
        ]
    )
    return response.choices[0].message.content

Code Generation Test

Task: Generate a REST API with authentication

prompt = """
Create a Python Flask REST API with:
1. User registration and login
2. JWT authentication
3. Protected endpoints
4. Input validation
5. Error handling
6. SQLAlchemy models
Include complete, production-ready code.
"""

claude_code = claude_completion(prompt)
gpt4_code = gpt4_completion(prompt)

Results:

MetricClaude 3 OpusGPT-4 TurboWinner
Code quality9/108/10Claude
Completeness10/109/10Claude
Best practices10/108/10Claude
Documentation9/107/10Claude
Time to generate45s28sGPT-4

Claude generated more complete code with better error handling and security practices.

Reasoning Test

Complex logic problem:

prompt = """
You have 3 boxes. One contains only apples, one contains only oranges, 
and one contains both. All boxes are labeled incorrectly. You can pick 
one fruit from one box. How do you correctly label all boxes?

Explain your reasoning step by step.
"""

claude_answer = claude_completion(prompt)
gpt4_answer = gpt4_completion(prompt)

Claude 3 Opus:

  • Correct answer: Yes
  • Reasoning clarity: Excellent
  • Step-by-step breakdown: Very detailed
  • Explanation quality: 10/10

GPT-4 Turbo:

  • Correct answer: Yes
  • Reasoning clarity: Good
  • Step-by-step breakdown: Adequate
  • Explanation quality: 8/10

Claude provided more thorough reasoning with better explanations.

Long Context Handling

Test with 150K token document:

# Load large document
with open('large_document.txt', 'r') as f:
    document = f.read()  # ~150K tokens

prompt = f"""
Document:
{document}

Questions:
1. Summarize the main arguments
2. Find contradictions
3. Extract key statistics
4. Identify missing information
"""

# Claude 3 Opus (200K context)
claude_analysis = claude_completion(prompt, model="claude-3-opus-20240229")

# GPT-4 Turbo (128K context - need to truncate)
truncated_doc = document[:100000]  # Approximate token limit
gpt4_analysis = gpt4_completion(f"Document:\n{truncated_doc}\n\n{prompt}")

Results:

  • Claude: Analyzed full document, found all contradictions
  • GPT-4: Missed information in truncated portion

Winner: Claude (larger context window)

Cost Comparison

Real production workload (1 month):

# Calculate costs
def calculate_cost(input_tokens, output_tokens, model):
    if model == "claude-3-opus":
        return (input_tokens / 1_000_000 * 15) + (output_tokens / 1_000_000 * 75)
    elif model == "gpt-4-turbo":
        return (input_tokens / 1_000_000 * 10) + (output_tokens / 1_000_000 * 30)

# Our usage (monthly)
input_tokens = 50_000_000  # 50M
output_tokens = 10_000_000  # 10M

claude_cost = calculate_cost(input_tokens, output_tokens, "claude-3-opus")
gpt4_cost = calculate_cost(input_tokens, output_tokens, "gpt-4-turbo")

print(f"Claude 3 Opus: ${claude_cost:,.2f}")
print(f"GPT-4 Turbo: ${gpt4_cost:,.2f}")

Results:

  • Claude 3 Opus: $1,500/month
  • GPT-4 Turbo: $800/month

Winner: GPT-4 (47% cheaper)

Speed Comparison

Benchmark: 1000-word article generation

import time

def benchmark_speed(model_func, prompt, iterations=20):
    times = []
    for _ in range(iterations):
        start = time.time()
        model_func(prompt)
        times.append(time.time() - start)
    return sum(times) / len(times)

prompt = "Write a 1000-word article about climate change solutions."

claude_time = benchmark_speed(
    lambda p: claude_completion(p, "claude-3-opus-20240229"),
    prompt
)

gpt4_time = benchmark_speed(
    lambda p: gpt4_completion(p, "gpt-4-turbo"),
    prompt
)

print(f"Claude 3 Opus: {claude_time:.2f}s")
print(f"GPT-4 Turbo: {gpt4_time:.2f}s")

Results:

  • Claude 3 Opus: 42.3s
  • GPT-4 Turbo: 28.7s

Winner: GPT-4 (32% faster)

Real-World Use Cases

1. Code Review:

def review_code_with_both(code):
    prompt = f"""
    Review this code for:
    1. Security vulnerabilities
    2. Performance issues
    3. Best practices violations
    4. Potential bugs
    
    Code:
    ```python
    {code}
    ```
    """
    
    claude_review = claude_completion(prompt)
    gpt4_review = gpt4_completion(prompt)
    
    return {
        "claude": claude_review,
        "gpt4": gpt4_review
    }

# Test
code = """
def process_payment(amount, card_number):
    # Process payment
    db.execute(f"INSERT INTO payments VALUES ({amount}, '{card_number}')")
    return True
"""

reviews = review_code_with_both(code)

Claude found:

  • SQL injection vulnerability
  • Missing input validation
  • No error handling
  • Storing card numbers (PCI compliance issue)
  • Missing transaction management

GPT-4 found:

  • SQL injection vulnerability
  • Missing error handling
  • No input validation

Winner: Claude (more thorough)

2. Technical Documentation:

def generate_docs(code):
    prompt = f"""
    Generate comprehensive API documentation for this code:
    
    {code}
    
    Include:
    - Function descriptions
    - Parameters
    - Return values
    - Examples
    - Error cases
    """
    
    return {
        "claude": claude_completion(prompt),
        "gpt4": gpt4_completion(prompt)
    }

Results:

  • Claude: More detailed, better examples
  • GPT-4: Faster, good enough for most cases

Claude 3 Sonnet Alternative

For cost-sensitive workloads:

def claude_sonnet_completion(prompt):
    message = claude_client.messages.create(
        model="claude-3-sonnet-20240229",
        max_tokens=4096,
        messages=[{"role": "user", "content": prompt}]
    )
    return message.content[0].text

# Cost: $3/1M input, $15/1M output (5x cheaper than Opus)

Claude 3 Sonnet vs GPT-4 Turbo:

  • Speed: Similar
  • Cost: Sonnet 60% cheaper
  • Quality: Sonnet slightly better
  • Context: Sonnet 200K vs GPT-4 128K

Production Recommendations

Use Claude 3 Opus for:

  • Complex reasoning tasks
  • Code generation and review
  • Long document analysis (>128K tokens)
  • High-stakes decisions
  • When quality > cost

Use GPT-4 Turbo for:

  • High-volume workloads
  • Real-time applications
  • Cost-sensitive projects
  • General-purpose tasks
  • When speed > quality

Use Claude 3 Sonnet for:

  • Best balance of cost/quality
  • Most production workloads
  • Long context needs
  • Better than GPT-4 Turbo at lower cost

Hybrid Approach

Use both strategically:

def smart_completion(prompt, task_type):
    if task_type == "code_review":
        return claude_completion(prompt, "claude-3-opus-20240229")
    elif task_type == "chat":
        return gpt4_completion(prompt, "gpt-4-turbo")
    elif task_type == "analysis":
        return claude_completion(prompt, "claude-3-sonnet-20240229")
    else:
        return gpt4_completion(prompt, "gpt-4-turbo")

# Route based on task
code_review = smart_completion(code, "code_review")  # Uses Claude Opus
chat_response = smart_completion(message, "chat")  # Uses GPT-4

Results Summary

CategoryClaude 3 OpusGPT-4 TurboWinner
Code Quality9/108/10Claude
Reasoning10/108/10Claude
Speed7/109/10GPT-4
Cost6/108/10GPT-4
Context Window200K128KClaude
Documentation9/107/10Claude
Versatility8/109/10GPT-4

Overall: Depends on use case

Our Production Setup

class AIRouter:
    def __init__(self):
        self.claude = anthropic.Anthropic(api_key=CLAUDE_KEY)
        self.openai = OpenAI(api_key=OPENAI_KEY)
    
    def complete(self, prompt, priority="balanced"):
        if priority == "quality":
            # Use Claude 3 Opus for best quality
            return self.claude_opus(prompt)
        elif priority == "speed":
            # Use GPT-4 Turbo for speed
            return self.gpt4_turbo(prompt)
        else:
            # Use Claude 3 Sonnet for balance
            return self.claude_sonnet(prompt)
    
    def claude_opus(self, prompt):
        msg = self.claude.messages.create(
            model="claude-3-opus-20240229",
            max_tokens=4096,
            messages=[{"role": "user", "content": prompt}]
        )
        return msg.content[0].text
    
    def claude_sonnet(self, prompt):
        msg = self.claude.messages.create(
            model="claude-3-sonnet-20240229",
            max_tokens=4096,
            messages=[{"role": "user", "content": prompt}]
        )
        return msg.content[0].text
    
    def gpt4_turbo(self, prompt):
        response = self.openai.chat.completions.create(
            model="gpt-4-turbo",
            messages=[{"role": "user", "content": prompt}]
        )
        return response.choices[0].message.content

# Usage
router = AIRouter()

# High-quality code review
review = router.complete(code_prompt, priority="quality")

# Fast customer support
response = router.complete(support_query, priority="speed")

# Balanced general use
result = router.complete(general_prompt, priority="balanced")

Lessons Learned

  1. No clear winner - Depends on use case
  2. Claude excels at reasoning - Better for complex tasks
  3. GPT-4 wins on speed/cost - Better for high volume
  4. Claude 3 Sonnet is sweet spot - Best balance
  5. Use hybrid approach - Route intelligently

Conclusion

Both models are excellent. Choose based on your priorities:

  • Quality-first: Claude 3 Opus
  • Cost-first: GPT-4 Turbo
  • Balanced: Claude 3 Sonnet

Key takeaways:

  1. Claude 3 Opus: Best reasoning and code quality
  2. GPT-4 Turbo: Faster and cheaper
  3. Claude 3 Sonnet: Best overall value
  4. Use hybrid routing for optimal results
  5. Test both with your specific workload

Don’t pick one. Use both strategically.