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ComparisonMay 20, 20259 min read

GPT-4o vs Claude 3.5 Sonnet: Which One Should You Use for Work?

Both models cost $20/month. We put them through 30 real work tasks, emails, code reviews, data analysis, long-form writing, to settle the debate.

Both GPT-4o and Claude 3.5 Sonnet cost $20/month. Both are described by their makers as best-in-class. In practice, they are meaningfully different tools that excel in different areas, and choosing the wrong one will noticeably slow you down.

The Test Setup

We ran 30 tasks across five categories: email writing, code review, data analysis, long-form content, and ad-hoc Q&A. Every task was judged blindly by three team members who did not know which model produced which output.

Writing: Claude Wins Clearly

Across email drafts, blog posts, and report writing, Claude 3.5 Sonnet was preferred 71% of the time. Its outputs feel more considered, less template-y, more aware of tone and audience. GPT-4o writes competently but predictably.

Coding: Too Close to Call

On code review and generation tasks, blind judges preferred GPT-4o 52% to 48%. Both models are genuinely excellent here. GPT-4o has a slight edge on multi-file context; Claude handles tricky refactors more gracefully.

Our Recommendation

If your work is primarily writing, research, and analysis: Claude 3.5 Sonnet. If you need image understanding, voice mode, or heavy coding with a large plugin ecosystem: GPT-4o. If you are not sure, start with Claude, it is the more thoughtful model.

Rankly AI editorial team

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