What is an ATS System? How Recruiting Software Works
Understand the gatekeeping technology that filters 70%+ of job applications before a human reads them.
Most job seekers have no idea what ATS systems are or how they work. If you're applying to jobs at established companies, an ATS system is likely the first gatekeeper—before any recruiter sees your resume. Understanding ATS is critical to modern job searching.
What Does ATS Stand For?
ATS stands for Applicant Tracking System. It's software that companies use to manage the hiring process: posting jobs, receiving applications, screening resumes, scheduling interviews, and tracking candidates through the entire recruitment pipeline.
How Does an ATS System Work?
When you submit your resume online, the ATS system automatically parses it (extracts text and data). It then analyzes your resume against the job requirements, looking for keywords, skills, education, and experience. The system assigns you a match score. If your score is above the company's threshold, your resume advances to a recruiter. If it's below, you're automatically rejected without human review.
What Do ATS Systems Actually Scan For?
- Keywords: Specific skills, tools, languages, certifications from the job posting (Python, AWS, Salesforce, etc.)
- Experience Level: Dates and tenure—ATS calculates years of experience and matches to "5+ years required"
- Education: Degree type (Bachelor's, MBA), field, school, and specific certifications
- Job Titles: Your past titles compared to industry standards. "Senior Developer" ranks differently than "Developer"
- Structure: Properly formatted sections (Work Experience, Education, Skills). ATS needs to parse your resume correctly
- Format Compatibility: Readable fonts, single-column layout, standard file types (DOCX, PDF)
Which Companies Use ATS?
Any large organization likely uses ATS. Fortune 500 companies almost universally use Workday or SAP SuccessFactors. Tech companies use Greenhouse or Lever. Government jobs use specialized ATS systems. If a company posts jobs on their own careers page (not LinkedIn or Indeed), they probably use ATS. Startups with under 50 employees may manually review resumes, but don't count on it.
How Many Resumes Get Filtered by ATS?
Studies suggest 70-80% of resumes are automatically rejected by ATS before a recruiter sees them. That number is even higher for popular roles (software engineer, product manager, data scientist). If you're applying to established companies and not getting callbacks, ATS filtering is likely the culprit. That's why ATS optimization is no longer optional—it's essential.
Frequently Asked Questions
Do all companies use ATS systems?
Not all, but most large companies (100+ employees) do. Startups and small companies often review resumes manually. Government jobs always use ATS. If you're targeting established companies, assume they use ATS.
Can you trick an ATS system?
You can optimize for ATS by using keywords and proper formatting. You can't reliably 'trick' modern systems—they're sophisticated. Focus on honest optimization that makes your resume more scannable for both ATS and humans.
Which ATS systems are most common?
Major platforms: Workday (used by 30% of Fortune 500), SAP SuccessFactors, Taleo (acquired by Oracle), Greenhouse, Lever, and iCIMS. Each has slightly different parsing logic, so general best practices work across most.