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Anthropic Claude Sonnet 4.6 vs OpenAI GPT-5.3-Codex vs DeepSeek V3.2: Performance Comparison

A comprehensive comparison of three leading AI models across performance metrics, cost efficiency, and response times.

Anthropic: Claude Sonnet 4.6

5.9

/ 10

vs

OpenAI: GPT-5.3-Codex

5.5

/ 10

Key Findings

Overall PerformanceAnthropic: Claude Sonnet 4.6

Leads with 5.9 overall score, outperforming competitors by 0.39-2.31 points

Response SpeedAnthropic: Claude Sonnet 4.6

Fastest at 469ms average latency, 3.5x faster than DeepSeek and 5.9x faster than GPT-5.3-Codex

Cost EfficiencyDeepSeek: DeepSeek V3.2

30x more cost-effective at $0.000447 per run vs $0.014+ for premium models

AccuracyAnthropic: Claude Sonnet 4.6

Highest accuracy score of 5.9, demonstrating superior precision in responses

Instruction FollowingAnthropic: Claude Sonnet 4.6

Perfect 5.9 score for following complex instructions and maintaining context

Specifications

SpecAnthropic: Claude Sonnet 4.6OpenAI: GPT-5.3-Codex
Provideranthropicopenai
Context Length1.0M400K
Input Price (per 1M tokens)$3.00$1.75
Output Price (per 1M tokens)$15.00$14.00
Max Output Tokens128,000128,000
Tieradvancedadvanced

Our Verdict

Claude Sonnet 4.6 dominates this comparison with superior performance and lightning-fast responses, making it the clear choice for applications prioritizing quality and speed. GPT-5.3-Codex offers competitive accuracy but suffers from prohibitively slow response times. DeepSeek V3.2 provides exceptional value for budget-conscious users willing to trade performance for cost savings.

Overview

The battle for AI supremacy continues with three compelling models: Anthropic: Claude Sonnet 4.6 vs OpenAI: GPT-5.3-Codex vs DeepSeek: DeepSeek V3.2. Each represents a different approach to large language model development, offering distinct advantages in performance, cost, and capabilities.

In this comprehensive evaluation, we examine how these models perform across critical metrics including accuracy, instruction following, response latency, and cost efficiency. The results reveal significant differences that can guide your model selection decision.

Benchmark Results

Our comparative evaluation assessed all three models on accuracy and instruction following capabilities. The results show a clear performance hierarchy, with notable differences in both overall scores and response characteristics.

ModelOverall ScoreRankAccuracyInstruction Following
Anthropic: Claude Sonnet 4.65.915.95.9
OpenAI: GPT-5.3-Codex5.5125.515.51
DeepSeek: DeepSeek V3.23.5933.593.59

The score spread of 2.31 points between the top and bottom performers indicates substantial differences in capability. Claude Sonnet 4.6 demonstrates superior performance across both evaluation criteria, while DeepSeek V3.2 trails significantly behind the two leading models.

Side-by-Side Model Analysis

Anthropic: Claude Sonnet 4.6

Claude Sonnet 4.6 emerges as the clear leader with an overall score of 5.9, ranking first in our evaluation. The model demonstrates exceptional consistency, achieving identical scores of 5.9 for both accuracy and instruction following. With an average latency of 469ms, it delivers the fastest response times among the three models. The model processes an average of 238 prompt tokens and generates 189 completion tokens per response, showing efficient token utilization.

OpenAI: GPT-5.3-Codex

GPT-5.3-Codex secures second place with an overall score of 5.51, maintaining competitive performance across both evaluation criteria. However, the model shows a significant latency disadvantage with an average response time of 2,745ms—nearly six times slower than Claude Sonnet 4.6. The model processes slightly fewer prompt tokens (215 average) but generates more completion tokens (225 average), indicating more verbose responses.

DeepSeek: DeepSeek V3.2

DeepSeek V3.2 ranks third with an overall score of 3.59, showing consistent but lower performance across accuracy and instruction following metrics. The model offers moderate latency at 1,629ms and demonstrates the most concise responses with only 146 average completion tokens. Despite lower performance scores, it processes a similar number of prompt tokens (216 average) as the other models.

Cost & Latency Analysis

Cost efficiency varies dramatically across the three models, creating important considerations for different use cases and budgets.

Anthropic: Claude Sonnet 4.6 operates at a total cost of $0.014196 per evaluation run, with a cost per output token of $0.018778. While delivering premium performance, it comes at the highest price point among the three options.

OpenAI: GPT-5.3-Codex offers nearly identical total costs at $0.014091 per run, with a slightly lower cost per output token of $0.015674. The similar pricing to Claude Sonnet 4.6 makes the significant latency difference a crucial differentiator.

DeepSeek: DeepSeek V3.2 presents exceptional value at just $0.000447 per evaluation run and $0.000764 per output token—roughly 30 times more cost-effective than the premium models. This dramatic cost advantage makes it attractive for budget-conscious applications despite lower performance scores.

Latency performance shows Claude Sonnet 4.6 leading with 469ms average response time, followed by DeepSeek V3.2 at 1,629ms, while GPT-5.3-Codex lags significantly at 2,745ms.

Use Cases

Claude Sonnet 4.6 excels in applications requiring the highest accuracy and fastest response times, making it ideal for real-time applications, customer service chatbots, and critical decision-support systems where performance justifies premium pricing.

GPT-5.3-Codex suits applications where high accuracy is essential but response time is less critical, such as code generation, detailed analysis tasks, and content creation where the extra processing time can be tolerated for quality results.

DeepSeek V3.2 serves well in cost-sensitive applications, bulk processing tasks, and scenarios where moderate accuracy suffices, such as basic content generation, simple question answering, or experimental projects with limited budgets.

Verdict

Claude Sonnet 4.6 establishes itself as the premium choice, delivering superior performance with the fastest response times, though at a higher cost. GPT-5.3-Codex offers competitive accuracy but suffers from significantly slower response times that may limit its practical applications. DeepSeek V3.2, while trailing in performance metrics, provides exceptional value for cost-conscious users who can accept lower accuracy in exchange for dramatic cost savings.

Backed by real data

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See every response, score, and evaluator judgment behind this comparison. All data from PeerLM's blind evaluation pipeline.

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Methodology

Evaluated using PeerLM's blind evaluation pipeline with 4 responses per model across 2 criteria.