How ATS Systems Actually Work (And Why 75% of Resumes Never Get Read)

You spent three hours on your resume. You tailored it to the job description. You hit apply. And then — silence. No call, no email, not even a rejection. This is the ATS black hole, and it swallows the majority of applications before a single human being sees them.

Applicant Tracking Systems (ATS) are software platforms used by over 98% of Fortune 500 companies and the vast majority of mid-sized businesses to manage job applications. Their job is to parse, rank, and filter resumes so that recruiters only see the most relevant candidates. The problem is that most resumes aren't formatted in a way ATS can actually read.

What an ATS actually does

When you hit submit, your resume doesn't go into a recruiter's inbox. It goes into a database. The ATS parses your document — breaking it into fields like job titles, companies, dates, skills, and education — and then ranks you against other applicants based on how well you match the job description.

The ranking is primarily keyword-based. The system compares the words in your resume to the words in the job description and scores the overlap. The closer the match, the higher your score. Candidates below a certain threshold are filtered out entirely.

Why most resumes fail the parse

• Tables and columns: ATS systems read left to right, top to bottom. A two-column layout often causes the system to merge text from both columns into one stream, creating gibberish.
• Headers and footers: Content placed in document headers or footers is frequently skipped entirely during parsing.
• Graphics and icons: Images, icons, and decorative elements are invisible to ATS — and if they contain text, that text is lost.
• Unusual fonts: Stick to standard system fonts. Exotic typefaces can cause character encoding errors that corrupt your content.
• PDFs saved incorrectly: A PDF exported from a design tool like Canva or Figma may be image-based, meaning the ATS sees a blank document.
• Non-standard section headings: If you label your work history 'What I've Done' instead of 'Experience', some ATS systems won't recognise it.

How the keyword ranking works

Different ATS platforms use different ranking algorithms, but the core logic is similar across all of them. They look for exact matches first, then variations, then semantic matches. That means the closer your language mirrors the job description, the better.

They also weight keywords differently. Skills listed in the job requirements section typically carry more weight than skills mentioned once in the job summary. The more prominent a keyword is in the posting, the more important it is to include it on your resume.

The sections that matter most

1. 1Skills section: This is the highest-signal section for ATS. A clearly labelled skills list makes it trivially easy for the system to find your capabilities.
2. 2Job titles: If your actual title differs from the industry-standard term, consider adding the common equivalent in parentheses.
3. 3Work experience bullet points: This is where keyword density matters most. Each bullet should be a specific, keyword-rich achievement.
4. 4Education: Include your full degree name, institution, and graduation year. ATS uses this to filter by minimum qualification.

What to do about it

The fix isn't complicated — but it requires intention. Start by reading the job description carefully and identifying the keywords that appear most often and most prominently. Then make sure those terms appear naturally in your resume, especially in your skills section and experience bullets.

Use a clean, single-column layout. Avoid tables, text boxes, and graphics. Save your resume as a text-based PDF or a .docx file, not an image-based export.

And use BylineCV's ATS scorer before you apply. It will tell you exactly how well your resume matches a specific job description, which keywords you're missing, and what score a recruiter would likely see.