Optimizing Resume Keywords for Both Human Readers and Machine Learning Models
In today's competitive job market, a well‑crafted resume must speak both to human hiring managers and to the algorithms that power Applicant Tracking Systems (ATS). This guide walks you through the science of keyword selection, the psychology of human readability, and the practical tools you can use—especially Resumly’s AI‑powered suite—to ensure your resume gets seen, parsed, and selected.
Why Keywords Matter to Humans and ATS
Recruiters skim resumes in seconds, looking for key phrases that match the job description. At the same time, ATS software parses the document, extracts nouns and verbs, and scores the match against the posting. If your resume lacks the right keywords, it may never reach a human eye.
- Human readers: They look for relevance, achievements, and industry jargon that signals expertise.
- Machine learning models: They evaluate term frequency, context, and semantic similarity. A well‑balanced keyword strategy satisfies both.
Stat: According to a 2023 Jobscan study, 75% of resumes are rejected before a human ever sees them because they fail ATS keyword criteria.
Understanding How ATS Parses Keywords
Most modern ATS use Natural Language Processing (NLP) to understand the meaning behind words, not just exact matches. However, they still rely heavily on exact phrase matching for ranking.
- Parsing stage – The ATS extracts text, removes formatting, and builds a token list.
- Matching stage – It compares tokens against the job posting’s required and preferred skills.
- Scoring stage – It assigns a relevance score based on frequency, proximity, and section placement.
Tip: Use Resumly’s free ATS Resume Checker to see how an ATS interprets your current draft.
Step‑by‑Step Guide to Researching the Right Keywords
1. Analyze the Job Posting
- Copy the entire posting into a text editor.
- Highlight required skills, preferred qualifications, and industry‑specific terms.
- Note any certifications, software names, or action verbs that repeat.
2. Leverage Keyword Tools
- Use Resumly’s Job‑Search Keywords tool to generate a list of high‑impact terms for the role.
- Cross‑reference with Google Trends or LinkedIn Skills to confirm popularity.
3. Prioritize by Relevance
| Priority | Example Terms |
|---|---|
| Core (must‑have) | "Python", "Project Management", "Agile Scrum" |
| Secondary (nice‑to‑have) | "Docker", "Data Visualization", "Stakeholder Management" |
| Soft Skills (contextual) | "Leadership", "Communication", "Problem‑Solving" |
4. Map Keywords to Your Experience
- For each term, write a bullet that demonstrates concrete achievement.
- Use action verbs (e.g., "engineered", "optimized", "led") to keep the language dynamic.
5. Test and Refine
- Paste the updated resume into the ATS Resume Checker.
- Aim for a match rate of 80%+ on required keywords.
Crafting Keywords for Human Readability
While stuffing a resume with keywords can please an ATS, it often alienates human readers. Here’s how to keep the narrative smooth:
- Do integrate keywords naturally within achievement statements.
- Don’t create a separate “Keyword Dump” section.
- Do use metrics (e.g., "increased sales by 30%") to give context.
- Don’t repeat the same phrase verbatim more than twice.
Example (poor): "Python, Python, Python, Python. Developed Python scripts..."
Example (good): "Developed Python scripts that automated data‑entry tasks, reducing processing time by 45%."
Balancing Keyword Density for Machine Learning Models
Machine learning‑driven ATS evaluate keyword density but also semantic relevance. Over‑optimization can trigger a “keyword stuffing” penalty.
| Metric | Recommended Range |
|---|---|
| Exact keyword frequency | 2‑4 mentions per 100 words |
| Synonym usage | Include 1‑2 related terms (e.g., "software development" for "coding") |
| Section placement | Place top keywords in Professional Summary, Core Competencies, and Experience sections |
Do: Use variations like “project management” and “managed projects”. Don’t: Insert the same phrase in every bullet.
Using Resumly Tools to Test and Refine Your Keywords
Resumly offers a suite of AI‑powered utilities that make keyword optimization painless:
- AI Resume Builder – Generates ATS‑friendly layouts and suggests high‑impact keywords.
- Buzzword Detector – Flags overused clichés and suggests fresher alternatives.
- Resume Readability Test – Ensures your language is clear for human readers (target grade‑8 level).
- Skills Gap Analyzer – Highlights missing competencies compared to a target job posting.
By iterating through these tools, you can achieve a balanced resume that satisfies both humans and AI.
Real‑World Example: Transforming a Generic Resume
Original Bullet (generic)
"Responsible for managing a team and delivering projects on time."
Optimized Bullet (keyword‑rich, human‑friendly)
"Led a cross‑functional team of 8 engineers to deliver Agile Scrum projects, achieving a 95% on‑time delivery rate while reducing budget overruns by 12%."
Why it works:
- Keywords: "Led", "cross‑functional team", "Agile Scrum", "on‑time delivery".
- Metrics: 95% delivery rate, 12% cost reduction.
- Readability: Clear, concise, and results‑focused.
Checklist: Optimized Resume Keyword Checklist
- Extract core and secondary keywords from the job posting.
- Verify each keyword appears 2‑4 times in the document.
- Use synonyms to avoid repetition.
- Place top keywords in Summary, Core Competencies, and Experience.
- Include quantifiable results for every achievement.
- Run the resume through Resumly’s ATS Checker and achieve 80%+ match.
- Run the Buzzword Detector and replace any flagged clichés.
- Ensure readability score is ≤ 8th‑grade level.
Common Mistakes to Avoid
| Mistake | Impact | Fix |
|---|---|---|
| Keyword stuffing – repeating the same term dozens of times | Triggers ATS penalties; looks spammy to humans | Use synonyms and limit frequency. |
| Over‑reliance on buzzwords (e.g., "team player", "hard‑working") | Reduces credibility; ATS may ignore them | Replace with concrete achievements. |
| Ignoring section hierarchy (placing keywords in footers) | ATS may miss them; humans never see them | Keep keywords in high‑visibility sections. |
| Using graphics or tables that ATS can’t read | Resume gets rejected before parsing | Stick to simple text formatting; Resumly’s AI Builder handles this automatically. |
Frequently Asked Questions
1. How many keywords should I include?
Aim for 2‑4 mentions of each core keyword per 100 words. Use secondary terms sparingly.
2. Do I need to match the exact phrasing from the job posting?
Exact matches boost ATS scores, but semantic equivalents (e.g., "project coordination" vs. "project management") also count for modern ML models.
3. Can I use the same resume for every application?
No. Tailor the keyword set for each posting. Resumly’s AI Resume Builder lets you swap sections quickly.
4. How do I know if my resume is too long?
Keep it to one page for <10 years experience, two pages otherwise. The Resume Readability Test helps you trim excess.
5. What if I don’t have a certification listed in the job posting?
Highlight transferable skills and relevant projects that demonstrate the same competency.
6. Are soft‑skill keywords important?
Yes, but pair them with actionable outcomes (e.g., "Improved team communication, resulting in a 20% reduction in project delays").
7. How often should I update my keyword list?
Review quarterly or whenever you target a new industry. Use the Career Personality Test to align your strengths with emerging terminology.
8. Does the ATS read PDFs?
Most modern ATS can parse PDFs, but simple formatting is safest. Resumly’s builder exports ATS‑friendly PDFs automatically.
Conclusion
Optimizing resume keywords for both human readers and machine learning models is no longer optional—it’s a must‑have strategy in the AI‑driven hiring landscape. By researching the right terms, weaving them naturally into achievement‑focused statements, and leveraging Resumly’s AI tools to test and refine, you can dramatically increase your chances of passing the ATS gate and impressing the hiring manager.
Ready to put these tactics into practice? Visit the Resumly homepage, try the AI Resume Builder, and run your draft through the ATS Resume Checker today. Your optimized resume is just a few clicks away!










