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charlie-morrison
charlie-morrison

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I Built a Free Resume ATS Checker (Client-Side Only, No Data Collection)

Most resume ATS checkers want your email, upload your resume to their servers, or paywall the results. I built one that runs entirely in your browser.

The Problem

If you've ever job-hunted, you know the drill:

  1. Upload resume to "free" ATS checker
  2. Enter your email
  3. Get spammed forever
  4. Results are behind a paywall anyway

I wanted something that actually checks your resume against a job description — without collecting any data.

The Solution

Resume ATS Score Checker — pure HTML + JavaScript, zero backend.

Your resume text never leaves your browser. No uploads, no accounts, no tracking.

What It Checks

The tool scores your resume out of 100 across several categories:

  • Length analysis — too short or too long?
  • Contact information — email, phone, LinkedIn present?
  • Section structure — does it have Education, Experience, Skills sections?
  • Action verbs — are you using strong verbs ("implemented", "designed") vs weak ones ("helped", "assisted")?
  • Quantified achievements — numbers beat vague claims ("increased revenue 40%" > "increased revenue")
  • Formatting — bullet points, reasonable line length
  • Keyword matching — paste a job description and see which keywords from the JD appear in your resume

The Interesting Part: Keyword Matching

This is the feature that makes it actually useful. ATS systems filter resumes by keyword match. If the job description says "Python, AWS, CI/CD" and your resume doesn't mention those exact terms — you're filtered out before a human ever sees it.

The tool does a simple but effective comparison:

  1. Extracts meaningful keywords from the job description (filtering out stop words)
  2. Checks which ones appear in your resume
  3. Shows you exactly what's missing

No AI, no fancy NLP — just practical string matching that mimics what most ATS systems actually do.

Technical Details

For anyone curious about the implementation:

  • Single HTML file — no build step, no dependencies
  • ~400 lines of JavaScript — readable, no framework
  • Responsive design — works on mobile
  • Color-coded results — green/yellow/red for pass/warn/fail

The scoring weights are opinionated but reasonable:

  • Resume length: 15 points
  • Contact info: 10 points
  • Section structure: 15 points
  • Action verbs: 15 points
  • Quantified achievements: 15 points
  • Formatting: 10 points
  • Keyword match: 20 points (highest weight, because it matters most for ATS)

Why Not Just Use ChatGPT?

You could paste your resume into ChatGPT and ask for feedback. But:

  1. Privacy — your resume contains personal info. This tool processes everything locally.
  2. Consistency — AI gives different advice each time. This tool gives objective scores.
  3. Speed — instant results vs. waiting for a response.
  4. Job-specific — the keyword matcher compares against a specific JD, not generic advice.

Try It

charliemorrison.dev/resume-checker

No signup. No email. Just paste and check.

If you find it useful, I also have a Job Search AI Toolkit with 50+ prompts for interviews, salary negotiation, and networking — but the checker is completely free, no strings.


Other free tools: LinkedIn Headline Generator | AI Developer Prompts (GitHub)

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