Head-to-head · frontier vs frontier

Claude Sonnet 4.5 Max vs GPT-5.2 Turbo: which model should you choose?

We compared Claude Sonnet 4.5 Max and GPT-5.2 Turbo on price, context window and 12 benchmarks. GPT-5.2 Turbo has the stronger average benchmark score; Claude Sonnet 4.5 Max is cheaper on a blended 3:1 basis.

Anthropic

Claude Sonnet 4.5 Max

Claude Sonnet 4.5 Max is a frontier model from Anthropic. It offers a 1,000,000-token context window, costs $19.90 per million input tokens and $95.47 per million output tokens, and averages 87.2 across the index's benchmark suite.

Input
$19.90 / 1M
Output
$95.47 / 1M
Context
1,000,000
Avg score
87.2
Open weights
No
Full Claude Sonnet 4.5 Max page
OpenAI

GPT-5.2 Turbo

GPT-5.2 Turbo is a frontier model from OpenAI. It offers a 1,000,000-token context window, costs $20.73 per million input tokens and $96.05 per million output tokens, and averages 87.4 across the index's benchmark suite.

Input
$20.73 / 1M
Output
$96.05 / 1M
Context
1,000,000
Avg score
87.4
Open weights
No
Full GPT-5.2 Turbo page

Specification comparison

SpecClaude Sonnet 4.5 MaxGPT-5.2 TurboEdge
Input price / 1M$19.90$20.73A
Output price / 1M$95.47$96.05A
Context window1,000,0001,000,000Tie
Max output65,5368,192A
Average score87.287.4B
Arena Elo1474.91500.3B
Open weightsNoNoTie

Benchmark comparison

Claude Sonnet 4.5 Max wins 5, GPT-5.2 Turbo wins 6, and 1 benchmarks are tied. The table shows the modelled score for each model and the gap.

BenchmarkClaude Sonnet 4.5 MaxGPT-5.2 TurboGapWinner
MMLU-Pro86.187.31.2GPT-5.2 Turbo
GPQA Diamond84.484.00.4Claude Sonnet 4.5 Max
SWE-bench Verified80.277.42.8Claude Sonnet 4.5 Max
HumanEval92.493.20.8GPT-5.2 Turbo
MATH-50092.892.70.1Claude Sonnet 4.5 Max
AIME 202585.486.71.3GPT-5.2 Turbo
LiveCodeBench82.882.50.3Claude Sonnet 4.5 Max
IFEval92.992.00.9Claude Sonnet 4.5 Max
TruthfulQA87.387.30.0Tie
HellaSwag93.195.52.4GPT-5.2 Turbo
MMMU82.083.31.3GPT-5.2 Turbo
Arena Elo1474.91500.325.4GPT-5.2 Turbo

Price analysis

On a blended 3:1 input-to-output basis, Claude Sonnet 4.5 Max costs about $38.79 per million tokens and GPT-5.2 Turbo costs about $39.56. Claude Sonnet 4.5 Max is roughly 2% cheaper than GPT-5.2 Turbo. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.

Both models list a 1,000,000-token context window. That is enough for long documents, large codebases and multi-step agent traces.

Verdict

Across 12 shared benchmarks, Claude Sonnet 4.5 Max wins 5, GPT-5.2 Turbo wins 6, and 1 are tied. On the index average, GPT-5.2 Turbo leads Claude Sonnet 4.5 Max by 0.2 points (87.4 versus 87.2).

The price picture favours Claude Sonnet 4.5 Max. The context picture is effectively a tie. Those two dimensions often matter more than a few benchmark points once a model is good enough for the task.

If you need a single default, start with GPT-5.2 Turbo for quality-sensitive work and Claude Sonnet 4.5 Max for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.

Choose Claude Sonnet 4.5 Max if

  • Unit cost matters and you want the cheaper blended price.
  • You need the larger 65,536-token output limit.

Choose GPT-5.2 Turbo if

  • You want the higher average benchmark score in this index.

FAQ

Is Claude Sonnet 4.5 Max better than GPT-5.2 Turbo?

On the index average, GPT-5.2 Turbo leads Claude Sonnet 4.5 Max by 0.2 points (87.4 versus 87.2). The better choice depends on price, context and your task. Claude Sonnet 4.5 Max wins 5 benchmarks, GPT-5.2 Turbo wins 6.

Which is cheaper, Claude Sonnet 4.5 Max or GPT-5.2 Turbo?

Claude Sonnet 4.5 Max is cheaper on a blended 3:1 basis at about $38.79 per million tokens, versus $39.56 for GPT-5.2 Turbo.

Which has the larger context window?

Both models list a 1,000,000-token context window.

Are these models open weights?

Claude Sonnet 4.5 Max is proprietary; GPT-5.2 Turbo is proprietary.

Which should I choose for production?

If you need a single default, start with GPT-5.2 Turbo for quality-sensitive work and Claude Sonnet 4.5 Max for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.

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