Leaderboard · Compare · Claude 3.5 Sonnet vs GPT-4o · Updated
Claude 3.5 Sonnet vs GPT-4o
Claude 3.5 Sonnet edges out GPT-4o on the composite (69.1 vs 66.8). The gap is meaningful but not decisive — see the per-benchmark breakdown below.
At a glance
| Spec | Claude 3.5 Sonnet | GPT-4o |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Released | 2024-10 | 2024-05 |
| Tier | general-purpose | general-purpose |
| License | Closed | Closed |
| Context window | 200k | 128k |
| $ in / out (per 1M) | $3.00 / $15.00 | $2.50 / $10.00 |
Benchmark scoreboard
Higher is better on every benchmark. Δ shows Claude 3.5 Sonnet − GPT-4o.
| Benchmark | Claude 3.5 Sonnet | GPT-4o | Δ |
|---|---|---|---|
| Chatbot Arena Elo | 1320 | 1380 | -60 |
| MMLU-Pro | 78.0 | 74.7 | +3.3 |
| GPQA Diamond | 65.0 | 53.6 | +11.4 |
| MATH | 78.3 | 76.6 | +1.7 |
| HumanEval | 92.0 | 90.2 | +1.8 |
| SWE-Bench Verified | 49.0 | 38.8 | +10.2 |
Numbers compiled from provider technical reports and Chatbot Arena snapshots — see methodology.
OpenRouter routes Claude 3.5 Sonnet, GPT-4o, and 100+ other LLMs behind a single API key — pay-as-you-go, no monthly minimum, fallback if a provider is down. Try OpenRouter → (affiliate · supports this site)
Claude 3.5 Sonnet vs GPT-4o: where each one wins
Claude 3.5 Sonnet is stronger on
- MMLU-Pro
- GPQA
- MATH
- HumanEval
- SWE-Bench
GPT-4o is stronger on
- Arena
Cost comparison
At 10M tokens/day (50/50 split), Claude 3.5 Sonnet costs ~$90.00/day vs $62.50/day for GPT-4o — GPT-4o is the cheaper pick at this volume.
Verdict
Claude 3.5 Sonnet edges out GPT-4o on the composite (69.1 vs 66.8). The gap is meaningful but not decisive — see the per-benchmark breakdown below.
If you can only pick one and your workload is unclear, route via OpenRouter and switch by request — same key, no lock-in.
Frequently asked questions
Which is better, Claude 3.5 Sonnet or GPT-4o?
Claude 3.5 Sonnet edges out GPT-4o on the composite (69.1 vs 66.8). The gap is meaningful but not decisive — see the per-benchmark breakdown below. Claude 3.5 Sonnet wins on MMLU-Pro, GPQA, MATH, HumanEval, SWE-Bench; GPT-4o wins on Arena.
What does Claude 3.5 Sonnet cost compared to GPT-4o?
At 10M tokens/day (50/50 split), Claude 3.5 Sonnet costs ~$90.00/day vs $62.50/day for GPT-4o — GPT-4o is the cheaper pick at this volume.
What is the context window of Claude 3.5 Sonnet vs GPT-4o?
Claude 3.5 Sonnet: 200k tokens. GPT-4o: 128k tokens. Claude 3.5 Sonnet has the larger window — useful for long-document RAG and full-codebase prompting.
Is Claude 3.5 Sonnet or GPT-4o open source?
Claude 3.5 Sonnet: closed / proprietary. GPT-4o: closed / proprietary.
Can I try Claude 3.5 Sonnet and GPT-4o on the same API key?
Yes — OpenRouter routes both models behind a single key, so you can A/B test Claude 3.5 Sonnet against GPT-4o without juggling provider accounts.
Model deep-dives: Claude 3.5 Sonnet · GPT-4o · Full leaderboard
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