Head-to-head · frontier vs frontier

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

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

Anthropic

Claude Opus 4.5 Turbo

Claude Opus 4.5 Turbo is a frontier model from Anthropic. It offers a 2,000,000-token context window, costs $19.57 per million input tokens and $106.60 per million output tokens, and averages 85.7 across the index's benchmark suite.

Input: $19.57 / 1M
Output: $106.60 / 1M
Context: 2,000,000
Avg score: 85.7
Open weights: No

Full Claude Opus 4.5 Turbo page

OpenAI

GPT-5.2

GPT-5.2 is a frontier model from OpenAI. It offers a 2,000,000-token context window, costs $19.71 per million input tokens and $85.71 per million output tokens, and averages 88.0 across the index's benchmark suite.

Input: $19.71 / 1M
Output: $85.71 / 1M
Context: 2,000,000
Avg score: 88.0
Open weights: No

Full GPT-5.2 page

Specification comparison

Spec	Claude Opus 4.5 Turbo	GPT-5.2	Edge
Input price / 1M	$19.57	$19.71	A
Output price / 1M	$106.60	$85.71	B
Context window	2,000,000	2,000,000	Tie
Max output	65,536	16,384	A
Average score	85.7	88.0	B
Arena Elo	1469.3	1478.0	B
Open weights	No	No	Tie

Benchmark comparison

Claude Opus 4.5 Turbo wins 2, GPT-5.2 wins 10, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.

Benchmark	Claude Opus 4.5 Turbo	GPT-5.2	Gap	Winner
MMLU-Pro	85.8	89.9	4.1	GPT-5.2
GPQA Diamond	81.9	84.9	3.0	GPT-5.2
SWE-bench Verified	75.0	80.2	5.2	GPT-5.2
HumanEval	89.8	91.0	1.2	GPT-5.2
MATH-500	93.2	90.6	2.6	Claude Opus 4.5 Turbo
AIME 2025	87.2	90.6	3.4	GPT-5.2
LiveCodeBench	78.5	79.7	1.2	GPT-5.2
IFEval	92.2	93.6	1.4	GPT-5.2
TruthfulQA	85.5	89.7	4.2	GPT-5.2
HellaSwag	92.8	92.6	0.2	Claude Opus 4.5 Turbo
MMMU	80.5	85.3	4.8	GPT-5.2
Arena Elo	1469.3	1478.0	8.7	GPT-5.2

Price analysis

On a blended 3:1 input-to-output basis, Claude Opus 4.5 Turbo costs about $41.33 per million tokens and GPT-5.2 costs about $36.21. GPT-5.2 is roughly 12% cheaper than Claude Opus 4.5 Turbo. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.

Both models list a 2,000,000-token context window. That is enough for long documents, large codebases and multi-step agent traces.

Verdict

Across 12 shared benchmarks, Claude Opus 4.5 Turbo wins 2, GPT-5.2 wins 10, and 0 are tied. On the index average, GPT-5.2 leads Claude Opus 4.5 Turbo by 2.3 points (88.0 versus 85.7).

The price picture favours GPT-5.2. 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 for quality-sensitive work, and check whether its price holds at your expected volume before committing.

Choose Claude Opus 4.5 Turbo if

You need the larger 65,536-token output limit.

Choose GPT-5.2 if

You want the higher average benchmark score in this index.
Unit cost matters and you want the cheaper blended price.

FAQ

Is Claude Opus 4.5 Turbo better than GPT-5.2?

On the index average, GPT-5.2 leads Claude Opus 4.5 Turbo by 2.3 points (88.0 versus 85.7). The better choice depends on price, context and your task. Claude Opus 4.5 Turbo wins 2 benchmarks, GPT-5.2 wins 10.

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

GPT-5.2 is cheaper on a blended 3:1 basis at about $36.21 per million tokens, versus $41.33 for Claude Opus 4.5 Turbo.

Which has the larger context window?

Both models list a 2,000,000-token context window.

Are these models open weights?

Claude Opus 4.5 Turbo is proprietary; GPT-5.2 is proprietary.

Which should I choose for production?