You spent hours writing your resume. You tailored it to the job description. You proofread it twice. And nobody ever saw it: because the applicant tracking system couldn’t read it.
Over 97% of Fortune 500 companies use an ATS to filter resumes before a human recruiter gets involved. Mid-size companies have adopted them just as aggressively. If you’re applying to jobs online, your resume is almost certainly being parsed by software first. Understanding how that software works: and what trips it up: is no longer optional.
Most ATS advice online is stuck in 2018. “Don’t use columns.” “Only submit in .docx.” “No color at all.” Some of that was true once. A lot of it is oversimplified now. Here’s what actually matters.
How Applicant Tracking Systems Actually Work
An ATS does three things with your resume: it parses it, it stores the parsed data, and it ranks or filters candidates based on that data.
Parsing is where most problems happen. The ATS reads your resume file and tries to extract structured information — your name, contact details, job titles, employers, dates, education, and skills. It maps that information into fields in a database. If it can’t figure out where your job title ends and your company name begins, it guesses. And it guesses wrong more often than you’d think.
Storage is straightforward. Your parsed data lives in the system alongside every other applicant. Recruiters can search, filter, and sort candidates based on the parsed fields.
Ranking varies by system. Some ATS platforms use keyword matching to score resumes against the job description. Others just filter by required qualifications (degree, years of experience, specific certifications). A few use more sophisticated matching algorithms that account for synonyms and related terms.
The key insight: an ATS doesn’t “reject” your resume the way most people imagine. It parses and stores it. If the parsing goes wrong, your data ends up in the wrong fields, your keywords don’t match and you become invisible in search results. The recruiter never finds you: not because you were rejected, but because you were misfiled.
The Major ATS Platforms (And Why It Matters)
Not all applicant tracking systems are created equal. The most common ones you’ll encounter are:
- Greenhouse. Popular with tech companies and startups. Relatively good at parsing modern resume formats.
- Lever. Common in mid-size tech companies. Handles PDFs well.
- Workday. Dominant in enterprise and Fortune 500. Notoriously rigid parsing. If your resume trips up any ATS, it’ll trip up Workday.
- iCIMS. Widely used in healthcare, retail and large corporations. Decent parsing but sensitive to non-standard formatting.
- Taleo (now Oracle Recruiting). One of the oldest systems. Still in use at many large companies. Less forgiving with creative formatting.
- BambooHR. Common in small to mid-size companies. Simpler system, less sophisticated parsing.
Why does this matter? Because you usually don’t know which ATS a company uses. Your resume needs to be readable by the least sophisticated parser in the group. Format for the lowest common denominator, and you’ll pass them all.
File Format: PDF vs. DOCX
This is one of the most debated questions in resume formatting, and the answer has changed over the years.
In 2026, PDF is fine for most ATS platforms. Modern parsing engines handle PDFs well. Greenhouse, Lever and iCIMS all parse PDFs reliably. Even Workday has improved its PDF parsing significantly.
DOCX is still the safest universal choice. If a job posting specifies a format, use that format. If it doesn’t, .docx gives you the widest compatibility. Some older ATS versions and some government application portals still handle .docx more reliably than PDF.
Never submit these formats: .pages, .odt, .jpg, .png, .rtf. Just don’t. A surprising number of applicants submit screenshots of their resumes or export from Apple Pages without converting. These either won’t parse at all or will produce gibberish.
One important PDF caveat: Make sure your PDF is text-based, not image-based. If you can highlight and copy text from your PDF, it’s text-based. If you can’t — for instance, if you scanned a printed resume or exported it as a flattened image: the ATS sees a blank page. This catches more people than you’d expect.
What Formatting Actually Breaks ATS Parsing
Here’s where the myths and reality diverge. Let’s go through the common advice and separate what matters from what doesn’t.
Headers and Footers
This one is real. Many ATS platforms skip content in document headers and footers entirely. If your name and contact information are in the header, some systems will parse your resume as having no name and no contact details. Put your name and contact info in the body of the document, not in the header or footer area.
Columns
Partially true, but nuanced. Single-column layouts are the safest. But many modern ATS platforms handle two-column layouts fine — as long as the columns are created with tables or proper column formatting, not with text boxes.
The problem with columns isn’t the visual layout. It’s how the content gets linearized when the ATS reads it. A two-column layout can cause the parser to read across both columns on the same line, jumbling your skills section with your job titles. Some systems handle this gracefully. Workday often doesn’t.
If you use a two-column layout, keep critical information (experience, education) in the main column and put supplementary information (skills, certifications, languages) in the sidebar. Test it by copying and pasting the text from your resume into a plain text editor. If it reads in the right order, an ATS will probably parse it correctly.
Tables
Use with caution. Tables for layout are a common issue. Some ATS platforms read table cells in unpredictable orders. A simple two-column table for your skills section is usually fine. A complex nested table layout for your entire resume is asking for trouble.
Graphics, Icons and Images
These are invisible to ATS. Any information conveyed only through an image — a skill rating bar, a pie chart of your competencies, an icon next to your phone number: doesn’t exist as far as the ATS is concerned. If you use icons, make sure the text is also present. If you use skill bars, also list the skill names as plain text.
Text Boxes
Avoid these. Text boxes in Word documents are frequently skipped or misread by ATS parsers. Content inside text boxes can end up at the end of the parsed output, completely out of order, or omitted entirely. This is one of the most reliable ways to break parsing.
Fonts and Special Characters
Stick to standard fonts. The ATS doesn’t care about your font choice visually — it’s extracting text, not rendering it. But some decorative fonts use non-standard character encodings that can cause garbled parsing. Calibri, Arial, Times New Roman and Helvetica are all safe.
For special characters: standard bullets and ampersands are fine. Avoid decorative bullets, arrows, or special Unicode characters for section dividers. They can parse as garbage characters.
Section Headers: What to Name Your Sections
ATS platforms look for standard section headers to figure out what type of content follows. Creative headers cause problems.
Use these standard headers:
- Experience (or Work Experience, or Professional Experience)
- Education
- Skills (or Technical Skills, or Core Competencies)
- Certifications (or Certifications & Licenses)
- Summary (or Professional Summary)
- Projects
- Volunteer Experience
Avoid these creative alternatives:
- “Where I’ve Been” instead of Experience
- “What I Know” instead of Skills
- “My Story” instead of Summary
- “The Impact” instead of Experience
It doesn’t matter how clever your section header is if the ATS files everything under “Other” because it didn’t recognize the label. Stick with conventional names.
Keyword Matching: How It Really Works
Keywords matter, but not the way most people think. You don’t need to stuff your resume with every word from the job description. Modern ATS platforms and recruiters are smarter than that.
Here’s how keyword matching typically works:
Hard skill matching is the most important. If the job requires “Python” and your resume doesn’t mention Python anywhere, you won’t appear in filtered results. Technical skills, tools, platforms and methodologies need to appear by name.
Job title matching matters for search. Recruiters often search their ATS by job title. If you were a “Client Success Manager” but the industry standard title is “Account Manager,” consider listing both: “Client Success Manager (Account Manager).” This helps you appear in searches.
Contextual matching is where it gets nuanced. Some modern systems (particularly Greenhouse and Lever) understand that “machine learning” and “ML” are the same thing. Others don’t. Use both the spelled-out version and the abbreviation the first time you mention a term.
Keyword stuffing is detectable. Some candidates paste the job description in white text at the bottom of their resume. Recruiters and ATS platforms catch this. It looks terrible when a recruiter opens the raw file or converts your resume to plain text. Don’t do it.
Where to place keywords: Your skills section is the most obvious place. But also weave them into your experience bullet points. “Built machine learning models using Python and TensorFlow” is better than just listing “Python” and “TensorFlow” in a skills section, because it shows context. Do both.
For a deeper look at which skills to include and how to present them, check out our breakdown of hard skills vs. soft skills on your resume.
The Right Resume Layout for ATS
Based on everything above, here’s the structural template that works across all major ATS platforms:
1. Contact Information (in the document body, not the header)
- Full name
- Phone number
- Professional email
- LinkedIn URL (optional but recommended)
- City and state (full address is unnecessary)
2. Professional Summary
- 3-4 lines
- Your title, years of experience and 2-3 key qualifications
- Include your target job title and top keywords naturally
3. Skills Section
- Group by category if you have many (Technical Skills, Tools, Certifications)
- Use the exact terms from job descriptions
- List both abbreviations and full terms where applicable
4. Professional Experience
- Job Title. Company Name. City, State. Start Date – End Date
- Use “Present” for current roles
- 3-5 bullet points per role
- Start each bullet with an action verb
- Include measurable results where possible
5. Education
- Degree. Institution. Graduation Year
- Include GPA only if recent graduate and above 3.5
- List relevant coursework only if you lack work experience
6. Additional Sections (as applicable)
- Certifications
- Projects
- Volunteer Experience
- Publications
This order works for most candidates. If you’re a recent graduate with limited experience, move Education above Professional Experience.
Date Formatting
This is a small detail that causes real parsing problems. ATS platforms expect dates in recognizable formats.
Safe formats:
- January 2024 – Present
- Jan 2024 – Present
- 01/2024 – Present
Risky formats:
- 2024 (just the year: the system may not parse the range correctly)
- Q1 2024 (quarters aren’t standard date parsing)
- Spring 2024 (seasons are ambiguous)
Use month and year. Be consistent throughout the document. Use an en dash or hyphen between start and end dates, not the word “to.”
Common Myths That Don’t Matter Anymore
“Never use color.” False. Color in section headers or your name is fine. ATS doesn’t parse color — it parses text. Color won’t help you, but a tasteful accent color won’t hurt you either. The ATS literally doesn’t see it.
“Only use one column.” Mostly outdated. As discussed, two columns are fine for most modern systems if implemented correctly. Just don’t put critical content in the sidebar column if you’re worried about older ATS platforms.
“ATS can’t read PDFs.” This was true for some systems a decade ago. In 2026, every major ATS handles text-based PDFs without issues.
“You need an exact keyword match percentage.” There’s no magic number. ATS platforms don’t all use the same scoring algorithm, and many don’t score at all — they just store and let recruiters search. Focus on including the right terms naturally rather than chasing a percentage.
Testing Your Resume’s ATS Compatibility
You can do a basic test yourself without paying for any tool:
- Open your resume in a PDF viewer
- Select All (Ctrl+A or Cmd+A) and Copy
- Paste into a plain text editor (Notepad, TextEdit in plain text mode)
- Read through it. Is the content in the right order? Are there garbled characters? Is anything missing?
If the plain text version reads correctly from top to bottom with all your information intact, an ATS parser will handle it well. If sections are jumbled, text is missing, or characters are garbled, fix the source document.
Avoiding the Most Common ATS Mistakes
The biggest mistakes people make with ATS aren’t about keywords or formatting tricks. They’re about basics that get overlooked. Using text boxes. Putting contact info in headers. Submitting image-based PDFs. Using creative section headers. These are the problems that make candidates invisible.
For a full rundown of resume mistakes that cost people interviews: including several that overlap with ATS issues: read our guide on common resume mistakes to avoid.
Putting It All Together
ATS optimization isn’t about gaming a system. It’s about making sure the software can read what you wrote. The same principles that make a resume ATS-friendly also make it easier for a human recruiter to scan: clear structure, standard sections, relevant keywords in context and a clean layout.
If you want to start from a template that’s already built to pass ATS parsing, 1Template designs its resume templates with ATS compatibility as a baseline requirement: clean formatting, standard section structures and text-based layouts that parse correctly across Greenhouse, Lever and the rest.
Stop worrying about whether your resume is “ATS-optimized.” Focus on three things: use a clean format, use standard section headers and include the right keywords from the job description. That’s 90% of ATS success right there.
