Compare · ModelsLive · 2 picked · head to head
GPT-5.3-Codex vs Claude Opus 4.6 (Fast)
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
GPT-5.3-Codex wins on 2/4 benchmarks
GPT-5.3-Codex wins 2 of 4 shared benchmarks. Leads in speed.
Category leads
speed·GPT-5.3-Codexagentic·Claude Opus 4.6 (Fast)
Hype vs Reality
Attention vs performance
GPT-5.3-Codex
#84 by perf·no signal
Claude Opus 4.6 (Fast)
#120 by perf·no signal
Best value
GPT-5.3-Codex
13.7x better value than Claude Opus 4.6 (Fast)
GPT-5.3-Codex
6.6 pts/$
$7.88/M
Claude Opus 4.6 (Fast)
0.5 pts/$
$90.00/M
Vendor risk
Who is behind the model
OpenAI
$840.0B·Tier 1
Anthropic
$380.0B·Tier 1
Head to head
4 benchmarks · 2 models
GPT-5.3-CodexClaude Opus 4.6 (Fast)
Artificial Analysis · Agentic Index
Claude Opus 4.6 (Fast) leads by +5.4
GPT-5.3-Codex
62.2
Claude Opus 4.6 (Fast)
67.6
Artificial Analysis · Coding Index
GPT-5.3-Codex leads by +5.0
GPT-5.3-Codex
53.1
Claude Opus 4.6 (Fast)
48.1
Artificial Analysis · Quality Index
GPT-5.3-Codex leads by +1.0
GPT-5.3-Codex
54.0
Claude Opus 4.6 (Fast)
53.0
SWE Atlas · Codebase QnA
Claude Opus 4.6 (Fast) leads by +0.7
GPT-5.3-Codex
32.6
Claude Opus 4.6 (Fast)
33.3
Full benchmark table
| Benchmark | GPT-5.3-Codex | Claude Opus 4.6 (Fast) |
|---|---|---|
Artificial Analysis · Agentic Index | 62.2 | 67.6 |
Artificial Analysis · Coding Index | 53.1 | 48.1 |
Artificial Analysis · Quality Index | 54.0 | 53.0 |
SWE Atlas · Codebase QnA | 32.6 | 33.3 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| GPT-5.3-Codex | $1.75 | $14.00 | 400K tokens (~200 books) | $48.13 |
| Claude Opus 4.6 (Fast) | $30.00 | $150.00 | 1.0M tokens (~500 books) | $600.00 |