An Applicant Tracking System is software that employers use to collect, parse, filter, and rank job applications. Over 98% of Fortune 500 companies and a growing majority of mid-size businesses rely on ATS platforms like Workday, Greenhouse, Lever, iCIMS, and Taleo to manage their hiring pipelines. When you click “Apply” on a job posting, your resume enters this system, and the ATS determines whether it moves forward or gets filtered out.

The ATS begins by parsing your resume file, extracting the raw text and attempting to map it into structured data fields such as name, contact information, work history, education, and skills. If your resume uses complex formatting like tables, multi-column layouts, embedded images, or non-standard fonts, the parser may scramble your content or skip entire sections. This single step is where most resumes fail.

After parsing, the ATS compares your extracted content against the job description, searching for matching keywords including specific skills, certifications, job titles, tools, and industry terminology. Your resume receives a numerical relevance score based on how many of these keywords appear and how they are used in context. Only resumes that exceed the employer’s score threshold advance to a recruiter for manual review. Understanding what the ATS checks is the first step toward ensuring your resume makes it through.

resumelon checks your resume against every one of these factors, giving you a clear score and specific fixes so you can submit with confidence.