Claude 3.5 Sonnet vs O3 Mini

Performance benchmarks + pricing comparison — updated April 2026

Claude 3.5 Sonnet

Anthropic

Previous generation Sonnet. Still excellent for coding tasks at the same price point.

Input$3.00/M
Output$15.00/M
Context200K tokens
Best ForCoding assistants, web development, data analysis
Benchmark72/100

O3 Mini

OpenAI

OpenAI's reasoning model at lower cost. Strong at math, coding, and science tasks.

Input$1.10/M
Output$4.40/M
Context200K tokens
Best ForMath, science, coding tasks requiring deep reasoning
Benchmark80/100

Benchmark Performance Comparison

Third-party benchmark scores — higher is better. Data sourced from SWE-bench, LiveCodeBench, HumanEval, and BigCodeBench.

BenchmarkClaude 3.5 SonnetO3 MiniLeader
Overall Score 72 80 o3-mini leads by 8pts
SWE-bench Verified 68 76 o3-mini leads by 8pts
LiveCodeBench 75 85 o3-mini leads by 10pts
HumanEval 90 94 o3-mini leads by 4pts
BigCodeBench 58 65 o3-mini leads by 7pts

Cost Comparison by Scenario

Estimated cost per project with 30% cache hit rate. Actual costs may vary based on usage patterns.

ScenarioClaude 3.5 SonnetO3 MiniSavings
Small Script (1K lines) $0.62 $0.17 O3 Mini saves $0.45 (72%)
Medium Feature (10K lines) $4.66 $1.27 O3 Mini saves $3.39 (73%)
Large Project (50K lines) $23.29 $6.33 O3 Mini saves $16.96 (73%)
Code Review (5K lines) $1.20 $0.30 O3 Mini saves $0.90 (75%)

Value Analysis (Price per Benchmark Score Point)

Lower is better — how much you pay for each point of benchmark performance.

ModelOverall ScorePrice per Score PointVerdict
Claude 3.5 Sonnet 72 $0.042/pt Higher cost per point
O3 Mini 80 $0.014/pt Better value

O3 Mini delivers the best value at $0.014 per score point.

Strengths & Weaknesses

Claude 3.5 Sonnet

  • + Balanced performance
  • + Computer use capability
  • + Artifact generation
  • - Older architecture
  • - Falling behind Sonnet 4

O3 Mini

  • + Excellent at competitive programming
  • + Strong algorithmic reasoning
  • - Optimized for reasoning, not chat

Verdict

O3 Mini wins on both price and performance — $1.10/M input with a benchmark score of 80/100.

For most developers, this is the clear choice between these two models.

Compare with Other Models