Claude 3.5 Sonnet vs GPT-4o: Benchmarks, Pricing, Verdict
Claude 3.5 Sonnet and GPT-4o are the two mid-2024 flagship models that most teams still weigh before committing to an AI provider, and the honest answer is that each one wins a different set of tasks. Claude 3.5 Sonnet, built by Anthropic, leads on coding accuracy and long-document work, while GPT-4o, built by OpenAI, leads on response speed, voice interaction, and native multimodal range.
Our AI Comparison testing focused on real developer and writing workflows rather than vendor benchmark charts alone. This guide breaks down features, performance, pricing, pros and cons, user sentiment, and the specific use cases where each model is the better pick.
Quick Comparison
Claude 3.5 Sonnet wins on context length, coding accuracy, and document analysis, while GPT-4o wins on response speed, voice conversations, and image generation. Both models accept text and image input, ship consumer apps at $20 per month, and expose nearly identical developer APIs. For a related comparison, see GPT-4o vs GPT-4.
| Attribute | Claude 3.5 Sonnet | GPT-4o |
|---|---|---|
| Developer | Anthropic | OpenAI |
| First released | June 2024 | May 2024 |
| Context window | 200,000 tokens | 128,000 tokens |
| Maximum output | 8,192 tokens | 16,384 tokens |
| Input types | Text, images, PDFs | Text, images, audio |
| Image generation | No | Yes, through DALL-E in ChatGPT |
| API price per million tokens | $3.00 input / $15.00 output | $2.50 input / $10.00 output |
| Knowledge cutoff | April 2024 | October 2023 |
| Best for | Coding, long documents, writing tone | Speed, voice, multimodal breadth |
The practical gap between these models is workflow fit rather than raw capability, because both clear the quality bar for general chat, drafting, and summarization.
What Is Claude 3.5 Sonnet?
Claude 3.5 Sonnet is Anthropic’s mid-tier model in the Claude 3.5 family, positioned between the faster Claude 3.5 Haiku and the earlier flagship Claude 3 Opus. Anthropic released it in June 2024 and shipped an upgraded version in October 2024 that improved coding scores and added a computer-use capability in public beta.
The model targets a 200,000-token context window, reads text, images, charts, and PDF files, and produces up to 8,192 output tokens per response. It powers the Claude apps, the Anthropic API, Amazon Bedrock, and Google Cloud Vertex AI, so the same model is available across three major clouds.
Anthropic reports that Claude 3.5 Sonnet beats Claude 3 Opus on most benchmarks while running about twice as fast at one-fifth of the cost. Readers weighing the older flagship can review Claude 3.5 Sonnet vs Claude 3 Opus for the full generational difference.
What Is GPT-4o?
GPT-4o is OpenAI’s “omni” model that processes text, image, and audio through a single network, with a focus on speed and low-latency conversation. OpenAI released it in May 2024 as the default model for ChatGPT and reduced its API price twice over the following months.
GPT-4o offers a 128,000-token context window, generates up to 16,384 output tokens, and reaches roughly 110 output tokens per second in typical use. It underpins ChatGPT Free, ChatGPT Plus, the OpenAI API, and Azure OpenAI Service.
Inside ChatGPT, GPT-4o adds live web browsing, the Canvas editor, Advanced Voice Mode, data analysis, and DALL-E image generation. Teams evaluating the smaller sibling can read GPT-4o vs GPT-4o Mini, and anyone migrating off the previous flagship can check GPT-4o vs GPT-4.
Feature Comparison
GPT-4o offers wider native modality and more built-in tools, while Claude 3.5 Sonnet offers longer context and the Artifacts workspace for iterative building. These 6 feature areas separate the two models in daily use.
- Context window: Claude 3.5 Sonnet holds 200,000 tokens against GPT-4o’s 128,000 tokens, roughly 150,000 words versus 96,000 words.
- Audio: GPT-4o supports native speech input and spoken output, while Claude 3.5 Sonnet has no voice mode.
- Image output: GPT-4o generates images through DALL-E in ChatGPT, while Claude 3.5 Sonnet only reads images.
- Web access: ChatGPT gives GPT-4o live browsing, while Claude 3.5 Sonnet answers from its April 2024 training data.
- Workspaces: Claude 3.5 Sonnet ships Artifacts for live previews, while GPT-4o ships Canvas for side-by-side editing.
- Computer use: the October 2024 Claude 3.5 Sonnet can operate a desktop in beta, while GPT-4o has no equivalent.
For most chat and API tasks the two feature sets overlap heavily, so the deciding factors become voice support, image output, and maximum context length.
Performance and Benchmarks
Claude 3.5 Sonnet leads on coding, graduate-level reasoning, and reading comprehension, while GPT-4o leads on math and raw generation speed. Vendor benchmarks use different prompting methods, so treat any gap under 3 points as statistical noise.
| Benchmark | Claude 3.5 Sonnet | GPT-4o |
|---|---|---|
| MMLU, undergraduate knowledge | 88.7% | 88.7% |
| HumanEval, code generation | 92.0% | 90.2% |
| MATH, problem solving | 71.1% | 76.6% |
| GPQA, graduate reasoning | 59.4% | 53.6% |
| DROP, reasoning over text (F1) | 87.1 | 83.4 |
| MGSM, multilingual math | 91.6% | 90.5% |
| MMMU, visual reasoning | 68.3% | 69.1% |
These figures come from Anthropic’s Claude 3.5 Sonnet launch table and OpenAI’s published GPT-4o results, measured with each vendor’s own harness. On SWE-bench Verified, which scores real GitHub issue resolution, the upgraded Claude 3.5 Sonnet reached 49.0%, well ahead of GPT-4o at about 33%.
GPT-4o answers faster in independent tests from Vellum and Artificial Analysis, with a time to first token near 0.5 seconds against roughly 1.2 seconds for Claude 3.5 Sonnet. Reviewers give Claude 3.5 Sonnet the edge on clean first-pass code and natural prose, and give GPT-4o the edge on latency and structured math, and a deeper model-by-model breakdown sits in our OpenAI Models Guide.
Pricing
GPT-4o is cheaper on the API at $2.50 per million input tokens and $10.00 per million output tokens, versus $3.00 and $15.00 for Claude 3.5 Sonnet. Consumer pricing is identical at $20 per month for Claude Pro and ChatGPT Plus.
| Cost item | Claude 3.5 Sonnet | GPT-4o |
|---|---|---|
| API input, per million tokens | $3.00 | $2.50 |
| API output, per million tokens | $15.00 | $10.00 |
| Consumer free tier | Claude Free, daily limits | ChatGPT Free, limited GPT-4o access |
| Consumer paid plan | Claude Pro, $20 per month | ChatGPT Plus, $20 per month |
| Batch discount | 50% | 50% |
Both providers lower the effective bill with prompt caching and a 50% batch-processing discount for non-urgent jobs. For very high volume, GPT-4o mini and Claude 3.5 Haiku cut per-token cost by more than 10 times while keeping most of the quality.
Pros and Cons
Claude 3.5 Sonnet trades speed and native audio for context length and coding accuracy, while GPT-4o trades some coding polish for speed, voice, and image output. The lists below summarize the trade-offs from official documentation and user reports.
Claude 3.5 Sonnet: 4 Pros and 3 Cons
Strengths:
- Highest coding accuracy in its class on HumanEval and SWE-bench Verified. For a related comparison, see Best AI Chatbot.
- A 200,000-token window that fits large codebases and long document sets.
- Natural writing tone that needs less manual editing.
- Artifacts panel for live document and code previews.
Weaknesses:
- No voice mode and no audio output.
- Slower generation at about 72 tokens per second.
- Higher API price than GPT-4o on both input and output.
GPT-4o: 4 Pros and 3 Cons
Strengths:
- Native voice conversations with low latency through Advanced Voice Mode.
- Image generation and image analysis in one model.
- Faster responses at roughly 110 tokens per second.
- Live web browsing and data analysis inside ChatGPT.
Weaknesses:
- Smaller 128,000-token context window.
- Weaker on complex, real-world software engineering tasks.
- An October 2023 knowledge cutoff when browsing is off.
User Reviews
Community feedback splits along the same line as the benchmarks, with developers favoring Claude 3.5 Sonnet for code and general users favoring GPT-4o for speed and voice. Sentiment here is drawn from Reddit, Hacker News, and review roundups published after both models shipped.
On coding forums, users repeatedly describe Claude 3.5 Sonnet as producing working code on the first attempt and needing fewer correction rounds. Writers echo this pattern, citing a more natural tone and stronger instruction-following on long, detailed prompts.
GPT-4o supporters point to Advanced Voice Mode, faster replies, and tighter integration with tools such as data analysis and image generation. Many power users keep both subscriptions and route coding tasks to Claude while sending everyday questions to ChatGPT. For a related comparison, see Claude vs ChatGPT.
Use Cases
Choose Claude 3.5 Sonnet for software engineering, large-document analysis, and brand-voice writing, and choose GPT-4o for voice assistants, rapid prototyping, and mixed-media tasks. The 4 scenarios below map common jobs to the better model.
- Refactoring a large codebase: Claude 3.5 Sonnet, for context size and code accuracy.
- Building a voice agent: GPT-4o, for native speech input and output.
- Summarizing a 200-page contract: Claude 3.5 Sonnet, for the 200,000-token window.
- Producing marketing images and copy together: GPT-4o, for DALL-E integration.
For chat-style research and quick drafting, both models perform well, and the choice often comes down to which app you already pay for. Broader roundups of the best AI chatbot and the best AI models place both in the top tier, and developers pairing a model with an editor can also read our best AI coding assistant guide.
Final Recommendation
Choose Claude 3.5 Sonnet for coding and long-context work, and choose GPT-4o for speed, voice, and multimodal output. Either model is a safe default for general assistant use.
Choose Claude 3.5 Sonnet if any of these 4 conditions apply:
- Code quality and fewer fix cycles are the priority.
- Inputs regularly exceed 100,000 tokens.
- Writing must match a defined tone with minimal editing.
- The workflow runs through Amazon Bedrock or Google Vertex AI.
Choose GPT-4o if any of these 4 conditions apply:
- Voice interaction is central to the product.
- Image generation and analysis happen in the same session.
- Response latency matters more than peak accuracy.
- One model must cover text, vision, and audio together.
Alternatives
The closest alternatives are Google Gemini 1.5 Pro, Claude 3 Opus, GPT-4o mini, and Claude 3.5 Haiku, each trading capability for cost or speed. Consider these 4 options when neither flagship is the right fit.
- Gemini 1.5 Pro: a 1-million-token context window for very large inputs.
- Claude 3 Opus: Anthropic’s slower, earlier flagship with strong reasoning.
- GPT-4o mini: near-GPT-4o quality at about one-twentieth of the input cost.
- Claude 3.5 Haiku: Anthropic’s fast, low-cost model for simple tasks.
For a product-level view rather than the raw model, our Claude vs ChatGPT comparison covers apps, message limits, and pricing in depth. Teams evaluating a third assistant can read Claude vs ChatGPT vs Gemini, and Anthropic users planning an upgrade can review Claude Sonnet 4 vs Claude 3.5 Sonnet.
Frequently Asked Questions
Is Claude 3.5 Sonnet better than GPT-4o?
Claude 3.5 Sonnet is better for coding, long documents, and writing tone, while GPT-4o is better for speed, voice, and image generation. Neither model wins every category, so the better choice depends on the workload.
Which is better for coding, Claude 3.5 Sonnet or GPT-4o?
Claude 3.5 Sonnet is better for coding. It scores 92.0% on HumanEval and 49.0% on SWE-bench Verified, both ahead of GPT-4o, and users report fewer correction cycles.
Is GPT-4o faster than Claude 3.5 Sonnet?
Yes, GPT-4o is faster. It generates about 110 tokens per second with a time to first token near 0.5 seconds, against roughly 72 tokens per second and 1.2 seconds for Claude 3.5 Sonnet.
Which model has a larger context window?
Claude 3.5 Sonnet has the larger context window at 200,000 tokens, compared with 128,000 tokens for GPT-4o. That difference is roughly 150,000 words versus 96,000 words.
Does Claude 3.5 Sonnet support image input?
Yes, Claude 3.5 Sonnet reads images, charts, and PDF files, but it cannot generate images. GPT-4o both reads and generates images through ChatGPT.
Is Claude 3.5 Sonnet cheaper than GPT-4o?
No, Claude 3.5 Sonnet is more expensive on the API at $3.00 and $15.00 per million input and output tokens, versus $2.50 and $10.00 for GPT-4o. The consumer plans cost the same $20 per month.
Final Verdict
Claude 3.5 Sonnet is the stronger pick for developers and heavy writers, while GPT-4o is the stronger pick for speed, voice, and multimodal projects. For a general assistant, either model handles daily tasks, so the deciding factors are context length, voice support, and API budget.
Claude 3.5 Sonnet earns the overall edge for professional work because coding accuracy and the 200,000-token window remove more friction than GPT-4o’s speed advantage adds. GPT-4o is the better answer when voice or image generation is central, or when the fastest possible response time is the top requirement.
