Claude 3.5 Sonnet vs GPT-4o
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
Claude 3.5 Sonnet specs · GPT-4o specs- PriceGPT-4o
GPT-4o is roughly 1.5× cheaper on output tokens ($10.00 vs $15.00 per 1M).
- Context windowClaude 3.5 Sonnet
Claude 3.5 Sonnet accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.
- BenchmarksClaude 3.5 Sonnet
Claude 3.5 Sonnet leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 92.0 vs 90.2.
- ModalitiesGPT-4o
GPT-4o supports 3 modalities (text, vision, audio) vs 2 for Claude 3.5 Sonnet.
- OpennessTie
Both are closed-weight, API-only.
It's a genuine coin-flip between Claude 3.5 Sonnet and GPT-4o: 2 category wins each, with the rest tied. GPT-4o is roughly 1.5× cheaper on output tokens ($10.00 vs $15.00 per 1M). Claude 3.5 Sonnet accepts 200K tokens vs 128K, 1.6× the room for long documents and codebases.
Claude 3.5 Sonnet leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 92.0 vs 90.2. They differ in modality coverage, Claude 3.5 Sonnet handles text, vision while GPT-4o handles text, vision, audio, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.
Claude 3.5 Sonnet is the newer of the two, released 5 months after GPT-4o, which usually means a more recent knowledge cutoff and updated safety post-training. Claude 3.5 Sonnet is usually picked for coding llm and code review workloads, while GPT-4o sees more deployments in chatbots and vision. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | Claude 3.5 Sonnet | GPT-4o |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Released | Oct 2024 | May 2024 |
| Modalities | text, vision | text, vision, audio |
| Context window | 200K tokens | 128K tokens |
| Max output | , | , |
| Input · 1M | $3.00 / 1M tokens | $2.50 / 1M tokens |
| Output · 1M | $15.00 / 1M tokens | $10.00 / 1M tokens |
| Knowledge cutoff | , | 2023-10 |
| Open weights | No | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day$31.50 vs $22.50
- Heavy usage, 1M in / 500k out per day$315 vs $225
- RAG workload, 5M in / 200k out per day$540 vs $435
Light usage, 100k in / 50k out per day: $31.50 vs $22.50 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $315 vs $225 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $540 vs $435 per month, model B comes out ahead.
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- Claude 3.5 Sonnet$1.05
- GPT-4o$0.750
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- MMLU,88.7
- HumanEval92.090.2
Claude 3.5 Sonnet fits when…
- Mature and battle-tested
- Strong code
- Long-context tasks, handles 200K tokens vs 128K for GPT-4o.
GPT-4o fits when…
- Native multimodal
- Mature SDK and tooling
- Cost-sensitive workloads, 1.5× cheaper than Claude 3.5 Sonnet on output tokens.
- Multimodal needs covering audio.
Consider Claude Opus 4.7
Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.
Frequently asked
Is Claude 3.5 Sonnet or GPT-4o cheaper?
GPT-4o is cheaper at $10.00 / 1M tokens per million output tokens, vs $15.00 / 1M tokens for Claude 3.5 Sonnet.Which has the larger context window?
Claude 3.5 Sonnet accepts 200K tokens vs 128K for GPT-4o.Is Claude 3.5 Sonnet or GPT-4o better for coding?
Both Claude 3.5 Sonnet and GPT-4o are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Neither model ships open weights, both are accessible only via their respective providers' APIs.When were Claude 3.5 Sonnet and GPT-4o released?
Claude 3.5 Sonnet was released by Anthropic on 2024-10-22. GPT-4o was released by OpenAI on 2024-05-13.
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