What Is an ATS and Why Is It Rejecting Your Resume?

The Invisible Gatekeeper

Before your resume ever reaches a hiring manager, it passes through software called an Applicant Tracking System (ATS). These systems are used by over 99% of Fortune 500 companies and the majority of mid-size businesses to automatically screen, sort, and reject candidates.

The hard truth: 75% of resumes are rejected by ATS software before a human ever reads them. That means three out of four job applicants are eliminated by an algorithm — not a person.

How ATS Actually Works

An ATS does several things when it receives your resume:

1. Parses your resume — It extracts text from your file and tries to identify your name, contact info, work history, education, and skills.
2. Scans for keywords — It compares your resume against the job description, looking for specific words and phrases the employer flagged as important.
3. Scores your match — It calculates a match percentage based on how many required keywords and qualifications your resume contains.
4. Filters candidates — Resumes below the score threshold are automatically rejected. Only the top-scoring resumes move forward to a human reviewer.

Why Your Resume Fails ATS

There are 5 common reasons a well-written resume gets rejected by ATS:

• Wrong keywords — You used "revenue growth" but the job says "sales performance." Same concept, different words — ATS doesn't know that.
• Fancy formatting — Tables, columns, text boxes, headers/footers, and graphics confuse ATS parsers. It can't read what it can't parse.
• Wrong file type — Some ATS systems struggle with .docx files. PDF is usually safer, but not always.
• Missing sections — No dedicated Skills section means the ATS can't find your skills, even if they're buried in your bullet points.
• Abbreviations — You wrote "PM" but the job listing says "Project Manager." Always spell out both.

Which Companies Use ATS?

Almost all of them. Here are some of the most widely used ATS platforms:

• Workday (used by Apple, Amazon, Bank of America)
• Taleo (used by Oracle, thousands of enterprises)
• Greenhouse (used by Airbnb, Dropbox, HubSpot)
• Lever (used by Netflix, Reddit, Spotify)
• iCIMS (used by FedEx, Target, T-Mobile)

If you're applying to any company with more than ~50 employees, assume ATS is in play.

The Fix: Know Your Score Before You Apply

The best thing you can do is check your ATS score before submitting any application. Find out which keywords you're missing, fix them, and resubmit — or tailor a new version for each role.

That's exactly what ResumeScore.ai does — in 30 seconds, for free.