Compare · ModelsLive · 2 picked · head to head
Claude Opus 4.8 vs GPT-5.3-Codex
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
Claude Opus 4.8 wins on 3/3 benchmarks
Claude Opus 4.8 wins 3 of 3 shared benchmarks. Leads in agentic · knowledge · coding.
Category leads
agentic·Claude Opus 4.8knowledge·Claude Opus 4.8coding·Claude Opus 4.8
Hype vs Reality
Attention vs performance
Claude Opus 4.8
#47 by perf·no signal
GPT-5.3-Codex
#101 by perf·no signal
Best value
GPT-5.3-Codex
1.6x better value than Claude Opus 4.8
Claude Opus 4.8
4.1 pts/$
$15.00/M
GPT-5.3-Codex
6.7 pts/$
$7.88/M
Vendor risk
Who is behind the model
Anthropic
$380.0B·Tier 1
OpenAI
$840.0B·Tier 1
Head to head
3 benchmarks · 2 models
Claude Opus 4.8GPT-5.3-Codex
APEX-Agents
Claude Opus 4.8 leads by +10.8
APEX-Agents · evaluates AI agents on complex, multi-step tasks requiring planning, tool use, and autonomous decision-making in realistic environments.
Claude Opus 4.8
42.5
GPT-5.3-Codex
31.7
PostTrainBench
Claude Opus 4.8 leads by +19.5
Claude Opus 4.8
37.2
GPT-5.3-Codex
17.8
WeirdML
Claude Opus 4.8 leads by +3.6
WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns.
Claude Opus 4.8
82.9
GPT-5.3-Codex
79.3
Full benchmark table
| Benchmark | Claude Opus 4.8 | GPT-5.3-Codex |
|---|---|---|
APEX-Agents APEX-Agents · evaluates AI agents on complex, multi-step tasks requiring planning, tool use, and autonomous decision-making in realistic environments. | 42.5 | 31.7 |
PostTrainBench | 37.2 | 17.8 |
WeirdML WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns. | 82.9 | 79.3 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| $5.00 | $25.00 | 1.0M tokens (~500 books) | $100.00 | |
| $1.75 | $14.00 | 400K tokens (~200 books) | $48.13 |