How ATS Systems Work
Automated filters reject 60 to 75% of applications. Here's how to get through.
Parsing
When you submit your resume, the ATS first parses it into structured data. It extracts your name, contact information, work history, education, and skills into separate fields in a database. Parsing accuracy depends heavily on your resume format, and simple, clean layouts with standard section headers parse best. Complex tables, multi-column layouts, headers/footers, and embedded images often confuse parsers, causing critical information to be lost or misplaced.
Keyword Matching
Once parsed, the ATS compares your resume content against the job description. It looks for exact keyword matches, semantic variations, and related terms. Keywords include hard skills (Python, Excel, Salesforce), certifications (PMP, CPA), job titles, and industry-specific terminology. Most systems also recognize synonym groups: for example, matching "customer service" with "client relations."
Scoring Thresholds
After matching, the ATS assigns a relevance score, typically a percentage or point total. Recruiters often set a threshold (e.g., 70%) and only review resumes that score above it. The score factors in keyword frequency, keyword placement (title vs. body), recency of experience, and how well your qualifications align with required vs. preferred criteria.
Common ATS Vendors
Greenhouse is popular among tech startups and mid-size companies, known for structured hiring workflows. Lever combines ATS and CRM features, favored by fast-growing companies. Workday dominates enterprise organizations with integrated HR suites. Taleo (Oracle) is one of the oldest systems and is prevalent in large corporations and government. Each vendor parses slightly differently, so a universally clean format is your best defense.
What Gets Filtered Out
Resumes get rejected for missing keywords, incompatible file formats (some systems struggle with .pages or heavily designed PDFs), missing required fields like location or years of experience, and overuse of acronyms without spelling them out. Graphics, logos, charts, and text boxes are invisible to most parsers. Always assume the ATS cannot read anything that isn't plain text in the document body.