Compare / head-to-head

Claude Opus 4.6vsGPT-5.2-Codex

Claude Opus 4.6 leads 6 of 10 shared benchmarks. GPT-5.2-Codex is 1.9x cheaper per token. Claude Opus 4.6 has the larger context window (1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
6 – 4
Claude Opus 4.6 leads
Cheaper per token
GPT-5.2-Codex
1.9x cheaper, input + output
Larger context
Claude Opus 4.6
1M tokens
Providers
2 providers
Anthropic · OpenAI
Claude Opus 4.6
Anthropic · released 2026-02-05
textvision
Context
1M
Max out
128K
Input /1M
$5 ↗
Output /1M
$25 ↗
Cached /1M
$0.5
Scores
46 · 11 core
GPT-5.2-Codex
OpenAI · released 2025-12-18
textvision
Context
400K
Max out
128K
Input /1M
$1.75 ↗
Output /1M
$14 ↗
Cached /1M
$0.175
Scores
13 · 2 core
Quality

Benchmark matrix

BenchmarkClaude Opus 4.6GPT-5.2-CodexΔEdge
Reported by both · 10
LiveBench Agentic Coding (LiveBench)49% ↗49.4% ↗-0.4 ptGPT-5.2-Codex
LiveBench Coding (LiveBench)78.2% ↗83.6% ↗-5.4 ptGPT-5.2-Codex
LiveBench Data Analysis (LiveBench)69.9% ↗78.2% ↗-8.3 ptGPT-5.2-Codex
LiveBench Instruction Following (LiveBench)63.3% ↗66.4% ↗-3.1 ptGPT-5.2-Codex
LiveBench Language (LiveBench)83.3% ↗73.7% ↗+9.6 ptClaude Opus 4.6
LiveBench Mathematics (LiveBench)89.3% ↗88.8% ↗+0.5 ptClaude Opus 4.6
LiveBench Reasoning (LiveBench)88.7% ↗77.7% ↗+11 ptClaude Opus 4.6
LMArena WebDev (LMArena)1545.9 ↗1338.9 ↗+207Claude Opus 4.6
OSWorld-Verified72.7% ↗38.2% ↗+34.5 ptClaude Opus 4.6
Terminal-Bench 2.065.4% ↗64% ↗+1.4 ptClaude Opus 4.6
Only Claude Opus 4.6 reports · 28
SWE-bench Verified80.8% ↗not reported——
GPQA Diamond91.3% ↗not reported——
AIME 202696.7% ↗matharenanot reported——
LMArena Elo1497.5 ↗not reported——
APEX-Agents (Mercor)46.3% ↗not reported——
ARC-AGI-2 (Verified)68.8% ↗not reported——
Chess Puzzles (Epoch AI run)17% ↗epoch runnot reported——
EBR-bench (Epoch AI run)12.7% ↗epoch runnot reported——
FrontierMath Tier 4 v2 (Epoch AI run)26.8% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)66% ↗epoch runnot reported——
Furniture Assembly (Epoch AI run)28.3% ↗epoch runnot reported——
GSO Opt@1 (GSO)37.3% ↗not reported——
LMArena Vision (LMArena)1299.4 ↗not reported——
MCP Atlas59.5% ↗not reported——
MMMLU91.1% ↗not reported——
MMMU-Pro (no tools)73.9% ↗not reported——
MMMU-Pro (with tools)77.3% ↗not reported——
Mystery Game Puzzles (Epoch AI run)25% ↗epoch runnot reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)94.4% ↗epoch runnot reported——
SAGE (Vals AI)51.6% ↗not reported——
SimpleBench (SimpleBench)67.6% ↗not reported——
SimpleQA Verified47% ↗epoch runnot reported——
SWE-bench Verified (Epoch AI run)78.7% ↗epoch runnot reported——
tau2-bench Banking Knowledge (Sierra)27.3% ↗not reported——
Tau2-bench Retail91.9% ↗not reported——
Tau2-bench Telecom99.3% ↗not reported——
Vending-Bench 2 (Andon Labs)8017.59 ↗not reported——
WeirdML (Håvard Tveit Ihle)78% ↗not reported——
Only GPT-5.2-Codex reports · 3
Cybersecurity Capture The Flag Challengesnot reported67.4% ↗——
SWE-Bench Pronot reported56.4% ↗——
SWE-Lancer IC Diamondnot reported76% ↗——
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Opus 4.6 minus GPT-5.2-Codex in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecClaude Opus 4.6GPT-5.2-CodexEdge
Context window1M tokens400K tokensClaude Opus 4.6
Max output128K tokens128K tokensTie
Input price / 1M$5 ↗$1.75 ↗GPT-5.2-Codex
Output price / 1M$25 ↗$14 ↗GPT-5.2-Codex
Cached input / 1M$0.5 ↗$0.175 ↗GPT-5.2-Codex
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$30$15.75GPT-5.2-Codex
Modalitiestext · visiontext · visionTie
Released2026-02-052025-12-18—
Cited benchmark scores4613—
Reliability

Provider status

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