Most recruiters never see 75% of the resumes submitted to a job posting. The bottleneck is not a person, it is software: the Applicant Tracking System. This guide covers exactly how ATS works, the 10 ways to get past it, the mistakes that kill your chances, and the file formats the system actually prefers.
What is an ATS?
An Applicant Tracking System (ATS) is software that companies use to sort through job applications. According to Jobscan, 98% of Fortune 500 companies use one. When you submit your resume online, it almost always goes through an ATS before any human reads it.
Here is what happens: the ATS scans your resume, pulls out your contact info, job titles, skills, and education, then compares everything against the job description. If your resume does not match enough keywords and criteria, it gets filtered out, and no recruiter ever sees it.
The good news: once you understand how ATS works, it is not hard to beat. You can check your resume right now with our .
How ATS works
Understanding the ATS pipeline helps you optimise your resume for each stage.
Resume Upload
You submit your resume through an online portal or email. The ATS receives and stores the file.
Parsing
The system extracts text from your resume, identifying sections like experience, education, and skills.
Keyword Match
Your resume is compared against the job description. The ATS looks for matching keywords and phrases.
Ranking
Resumes are scored and ranked. Top-scoring resumes are forwarded to recruiters for review.
What the parser actually does (in 5 steps)
Understanding the parser step-by-step makes every optimisation decision obvious. Here is what happens between your upload click and the candidate record in the recruiter's database.
- 1
Text extraction
The parser converts your PDF/DOCX into a flat text stream. Selectable-text PDFs extract perfectly; image-based PDFs extract nothing (they have no text layer). Complex column layouts extract top-to-bottom left-to-right, often interleaving unrelated content.
- 2
Section recognition
The parser looks for standard section headings ("Experience", "Education", "Skills") to chunk the text into logical blocks. Non-standard headings ("What I have been up to", "My toolbox") get flagged as unknown and the content may be dropped.
- 3
Entity extraction
Within each section, the parser pulls out structured entities: company names, job titles, employment dates (in multiple formats), school names, degrees, and a flat list of skills. Any of these that fail regex match are stored as "unstructured" which recruiters cannot search against.
- 4
Normalisation
The parser normalises variants: "JavaScript" and "JS" map to the same skill entity on modern parsers. Older ones (iCIMS pre-2020, legacy Taleo) do not normalise, which is why listing both the acronym and the full form helps.
- 5
Keyword matching + ranking
Finally, the recruiter runs searches like "Python AND (React OR Vue) AND NOT intern". Your candidate record either matches or it does not. The rank is based on match density and optional recency weighting.
Any optimisation you make should map back to one of these 5 stages. Stuck at stage 1 (text extraction)? That is a file format issue. Losing content at stage 2? Your headings are non-standard. Failing at stage 5? You do not have enough JD-matched keywords.
ATS statistics that matter
of resumes are filtered out by ATS before a recruiter ever reads them (Jobscan, 2024)
of Fortune 500 companies use an ATS to screen applicants (Jobscan)
applications per corporate job posting on average (Glassdoor, 2024)
is the average time a recruiter spends on an initial resume scan (Ladders, 2024)
10 ways to get past ATS screening
These are the tactics that actually work. Each one addresses a specific reason resumes get filtered out.
Use Relevant Keywords
Mirror the exact language from the job description. Include both spelled-out terms and acronyms (e.g., "Search Engine Optimization (SEO)").
Stick to Standard Headings
Use conventional section headings like "Work Experience," "Education," and "Skills" that ATS systems expect.
Keep Formatting Simple
Avoid complex layouts, columns, text boxes, headers/footers, and fancy formatting that can confuse parsers.
Submit as PDF or DOCX
These are the most widely supported formats. Check the job posting for any format preference.
Avoid Images and Tables
ATS cannot read text embedded in images, graphics, charts, or complex tables.
Use Strong Action Verbs
Start bullet points with impactful verbs like "Led," "Developed," "Implemented," "Achieved," and "Optimised."
Quantify Your Achievements
Use numbers and metrics to demonstrate impact: percentages, dollar amounts, team sizes, and time saved.
Tailor Each Application
Customise your resume for every job. One-size-fits-all resumes score poorly with ATS keyword matching.
Proofread Carefully
Typos and misspellings can prevent keyword matches. Double-check all text, especially technical terms.
Use an ATS-Optimised Template
Start with a template that is already built for ATS compatibility. ResumeBuildz 20 templates are tested against real ATS parsers.
Common ATS mistakes to avoid
Using Creative File Formats
Submitting resumes as JPG, PNG, or in portfolio formats that ATS cannot parse.
Stuffing Keywords Unnaturally
Hiding white text or cramming keywords out of context gets flagged or ignored by modern ATS.
Using Only Graphics and Icons
Replacing text with icons for contact info, skills ratings as bars, or image-based layouts.
Ignoring Job Description Language
Using different terminology than the job posting, even if they mean the same thing.
Multi-Column Complex Layouts
Fancy two or three-column designs can scramble the reading order for ATS parsers.
ATS-friendly file formats
| Feature | DOCX | Other (JPG, PNG) | |
|---|---|---|---|
| ATS Compatibility | High | Highest | None |
| Formatting Preserved | Excellent | Good | N/A |
| Parsing Accuracy | Good | Best | Not Supported |
| Universal Support | Yes | Yes | No |
| Recommended | Yes | Yes | No |
Per-system tuning
Different ATS platforms have different quirks. You can usually identify which system a company uses by looking at the URL of the application page. Then tune accordingly.
Workday
URL pattern: myworkdayjobs.com
Most common for Fortune 500 HR. Strong modern parser. Handles PDF and DOCX equally well. Very strict about exact skill-string matches. Tip: include both the exact JD phrasing and common synonyms.
Greenhouse
URL pattern: greenhouse.io, boards.greenhouse.io
Standard in tech startups. Excellent parser. Often lets you paste plain text directly (useful for sanity-checking your content).
Lever
URL pattern: jobs.lever.co
Common in mid-size tech. Weights the skills section heavily. Ingests LinkedIn data automatically; ensure your profile and resume tell the same story.
iCIMS
URL pattern: icims.com
Used by large US enterprises. Older parser, more fragile. Avoid tables, avoid multi-column layouts, keep headings standard.
Taleo
URL pattern: taleo.net
Oldest of the major platforms. Still used by legacy banks and government. Sometimes prefers DOCX over PDF. Spell out every acronym on first use. Simple formatting wins.
SmartRecruiters
URL pattern: jobs.smartrecruiters.com
Growing presence in mid-market. Modern parser; handles both PDF and DOCX well. Skills section parsing is stronger than experience parsing.
Testing your resume manually (no tool needed)
A 2-minute manual check that tells you almost everything an ATS will see.
- Open your PDF and select-all. If the entire page highlights as one block, you have an image-based PDF. Re-export with selectable text.
- Copy, paste into Notepad or TextEdit. Whatever the ATS sees is now in front of you. Read it top to bottom.
- Check the reading order. Do job titles sit with their correct employer? Or is your 2022 title showing under your 2019 employer? Multi-column layouts break here.
- Look for missing content. If bullets or sections are missing from the Notepad version, they will be missing from the ATS record too.
- Search for key terms. Use Ctrl+F on the Notepad version to find each skill listed in the JD. Missing ones need to be added or rephrased.
This simple test catches 80% of parser-level problems. The remaining 20% (keyword density, ranking) is what our free 12-point ATS checker addresses.
External references
Further reading on this topic from independent sources. All external links open in a new tab.
Frequently asked questions
Does every company use an ATS?+
Will an ATS reject my resume for typos?+
Is PDF or DOCX better for ATS?+
How do I know if my resume passed the ATS?+
Does the ATS read my LinkedIn profile?+
Can I game the ATS with hidden white-text keywords?+
How long does ATS screening take?+
Check your resume's ATS score
Upload your resume or build one from scratch. Our 12-point ATS checker shows exactly what to fix. Browse our ATS-friendly templates or read our resume writing tips.