Anthropic: Claude Opus 4 vs OpenAI: GPT-5 Codex: Which AI Model Is Better?
Updated March 24, 2026· Based on independent benchmark data
Quick Verdict
Anthropic: Claude Opus 4 and OpenAI: GPT-5 Codex are virtually tied on intelligence (46.5 vs 44.6). OpenAI: GPT-5 Codex is 12.0x cheaper at $1.25/1M tokens vs $15/1M. For speed, OpenAI: GPT-5 Codex wins at 170 tok/s vs 44 tok/s.
Head-to-Head Comparison
| Metric | Anthropic: Claude Opus 4 | OpenAI: GPT-5 Codex |
|---|---|---|
| Intelligence Score | 46.5 | 44.6 |
| Coding Score | 47.6 | 38.9 |
| Math Score | N/A | 98.7 |
| Speed (tok/s) | 44 tok/s | 170 tok/s |
| Latency (TTFT) | 1.94s | 4.79s |
| Input Price / 1M tokens | $15 | $1.25 |
| Output Price / 1M tokens | $75 | $10 |
| Context Window | 200K | 400K |
| Max Output Tokens | 32K | 128K |
| Input Modalities | Image + Text + File | Text + Image |
| Output Modalities | Text | Text |
| Free Tier | No | No |
Detailed Analysis
Intelligence & Quality
Anthropic: Claude Opus 4 and OpenAI: GPT-5 Codex perform similarly on overall intelligence, scoring 46.5 and 44.6 respectively. For coding tasks, Anthropic: Claude Opus 4 has the edge with a coding score of 47.6 vs 38.9.
Speed & Latency
OpenAI: GPT-5 Codex generates output significantly faster at 170 tok/s compared to Anthropic: Claude Opus 4's 44 tok/s, making it 3.8x faster for streaming responses. Time to first token is 1.94s for Anthropic: Claude Opus 4 vs 4.79s for OpenAI: GPT-5 Codex, which affects perceived responsiveness in interactive applications.
Pricing
OpenAI: GPT-5 Codex is more affordable at $1.25/1M input tokens ($10/1M output), while Anthropic: Claude Opus 4 costs $15/1M input ($75/1M output). That makes Anthropic: Claude Opus 4 12.0x more expensive per token, which can add up significantly at scale. For a typical workload of 100 requests per day at 2,000 tokens each, Anthropic: Claude Opus 4 would cost approximately $90.00/month vs $7.50/month for OpenAI: GPT-5 Codex in input costs alone.
Context Window
OpenAI: GPT-5 Codex offers a larger context window at 400K tokens compared to Anthropic: Claude Opus 4's 200K. For output length, OpenAI: GPT-5 Codex can generate up to 128K tokens per response vs 32K for Anthropic: Claude Opus 4.
Best Use Cases
Choose Anthropic: Claude Opus 4 when you need stronger coding performance (47.6). Choose OpenAI: GPT-5 Codex when you need faster output (170 tok/s), lower cost.
Choose Anthropic: Claude Opus 4 if:
- ✓You need higher intelligence (score: 46.5 vs 44.6)
- ✓You prioritize coding performance (score: 47.6 vs 38.9)
- ✓You want lower latency (1.94s vs 4.79s TTFT)
Choose OpenAI: GPT-5 Codex if:
- ✓You need faster throughput (170 tok/s vs 44 tok/s)
- ✓Budget is a concern ($1.25/1M vs $15/1M)
- ✓You need a larger context window (400K vs 200K)
Frequently Asked Questions
Is Anthropic: Claude Opus 4 better than OpenAI: GPT-5 Codex for coding?
Anthropic: Claude Opus 4 scores higher on coding benchmarks (47.6 vs 38.9), making it the better choice for programming tasks.
Which is cheaper, Anthropic: Claude Opus 4 or OpenAI: GPT-5 Codex?
OpenAI: GPT-5 Codex is cheaper at $1.25/1M input tokens vs $15/1M for Anthropic: Claude Opus 4.
Is Anthropic: Claude Opus 4 faster than OpenAI: GPT-5 Codex?
OpenAI: GPT-5 Codex is faster, producing output at 170 tok/s compared to Anthropic: Claude Opus 4's 44 tok/s.
Can Anthropic: Claude Opus 4 process images?
Yes, Anthropic: Claude Opus 4 supports image input. OpenAI: GPT-5 Codex also supports images.
Which has a larger context window, Anthropic: Claude Opus 4 or OpenAI: GPT-5 Codex?
OpenAI: GPT-5 Codex has a larger context window at 400K compared to Anthropic: Claude Opus 4's 200K.
Should I use Anthropic: Claude Opus 4 or OpenAI: GPT-5 Codex?
Both models perform similarly on intelligence benchmarks. Choose based on specific needs: pricing, speed, context window, or provider ecosystem.
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Benchmark data by Artificial Analysis
Data last synced: March 24, 2026