Best AI for Resume and Cover Letter (I Tested 6 Models Blind)

What is the best AI for your resume and cover letter? I tested 6 AI models blind, one from each major model family plus an open weight model, to see which one tailors a resume to a job description the way a recruiter wants to see it.

I get asked every week which AI to use for resume tailoring: ChatGPT, Claude, Gemini, or Grok? Free or paid? So I ran an experiment. Every model got the same template resume, the same job description, the same example tailored resume and cover letter, and the same prompt. I scored each output blind, then compared my scores with two AI judges (Claude Opus 5.5 and GPT-5.6 Sol) and Jev, a yes or no decision API that checks rules like headline format and a one-page cover letter.

The AI models tested:

Claude Opus 5.5 (Anthropic)Claude Sonnet 5.5 (Anthropic)Gemini 3.8 Flash (Google)GPT-6 Sol (OpenAI, ChatGPT)Grok (xAI)An open weight model

I also share what each one costs and how fast it runs, so you can decide if paying for AI is worth it.

In this episode you'll learn:

Which AI model is best for tailoring a resume to a job descriptionChatGPT vs Claude vs Gemini vs Grok for resumes and cover lettersWhether free AI models are good enough for job applications or worth paying forWhat a strong resume headline and highlights section look like to a recruiterThe AI writing habits that make a cover letter unusableWhy my human scores disagreed with the AI judges

See every output side by side, plus the template resume, job description, and example inputs, in the Model Bake-Off on the Biotech Career Coach website under Learn.

https://biotechcareercoach.com/

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