15 Critical ATS Mistakes to Avoid (and How to Fix Them)

The formatting and content mistakes that stop an applicant tracking system from reading your resume properly, each with a concrete fix.

Published · Updated · 7 min read

Table of Contents

  1. Introduction: The Hidden Cost of ATS Mistakes
  2. The 15 Most Common ATS Mistakes (by Category)
  3. ATS Parsing Test Methods
  4. Prevention Checklist
  5. Real-World Mini Case Studies
  6. FAQ
  7. Conclusion & CTA

Introduction: The Hidden Cost of ATS Mistakes

Most mid-to-large employers run résumés through an Applicant Tracking System (ATS) before a human ever sees them. Small formatting and export mistakes can cause missing sections, garbled dates, or invisible skills, keeping qualified candidates out of recruiter searches. The good news: every common ATS issue has a simple, repeatable fix—especially if you design with single-column structure, plain text, and mobile readability in mind.

If you're new to ATS-friendly fundamentals or want templates you can adapt, start here:

The 15 Most Common ATS Mistakes (by Category)

A) Formatting Mistakes

1) Using tables for layout Tables can scramble reading order and hide content from parsers.

Before

| Skills           | Experience (2022–2026)            |
| Python, SQL      | Built dashboards; A/B testing ... |

After

Skills: Python, SQL, dbt, BigQuery, Looker
Experience
Company — City (2022–2026) | Data Analyst
• Built dashboards; led A/B testing...

Fix: Convert tables to simple headings + bullet lists (single column).

2) Two-column or sidebar templates Sidebars often rely on columns/text boxes that break the left-to-right flow.

Before

[Sidebar] Skills, Contact
[Main]   Experience, Education

After

Contact (in body)
Summary
Skills
Experience
Education

Fix: Use a single column. Keep contact info at the top in the body.

3) Text boxes and shapes Word/Docs text boxes don't always export cleanly; content can vanish.

Before

[Text Box] Certifications: AWS CCP (2023)

After

Certifications
• AWS Certified Cloud Practitioner (2023)

Fix: Replace text boxes/shapes with standard paragraphs and bullets.

4) Headers/footers for contact info Some parsers ignore header/footer regions.

Before

[Header] First Last | email@… | (555) 555-5555

After

First Last
City, Country · [email protected] · (555) 555-5555 · linkedin.com/in/firstlast

Fix: Place contact details in the document body at the top.

5) Graphics, icons, logos in the body Images add file weight and parsing risk without keyword value.

Before: Title line with icons and a headshot After: Text-only headings, no icons Fix: Keep the résumé text-first; showcase visuals on your portfolio.

B) File Format Mistakes

6) Image-only or scanned PDFs If you can't select/copy text, the parser can't either.

Before: Export via "Print to PDF" from a scan (image layer only) After: Export a text-based PDF (or DOCX if the posting asks for Word) Fix: Ensure text is selectable; avoid scans/screenshots.

7) Bloated or non-standard exports Oversized PDFs or password-protected files may fail.

Before: 8MB PDF with embedded images After: A 200–500KB text-based PDF Fix: Remove graphics; use standard fonts; compress if needed.

8) Wrong file type for the portal Some portals still ask for .docx; a few restrict file types outright.

Before: .pages, .odt, or exotic formats After: Text-based PDF (default), or .docx when the posting asks for Word Fix: Follow the posting. Default to a text-based PDF when it says nothing.

C) Content Mistakes

9) Missing must-have keywords No keywords = poor search visibility.

Before

Responsible for infrastructure tasks. Worked on servers.

After

Migrated 42 services from EC2 to EKS with no customer-visible downtime; cut monthly compute spend 31% by rightsizing and adopting spot nodes.

Fix: Pull terms from the JD and integrate naturally (see keyword guide).

10) Keyword stuffing or hidden text Over-stuffing reads poorly; white-on-white text can get you flagged.

Before

SQL SQL SQL SQL SQL (hidden at bottom)

After

Automated SQL models for marketing cohort analysis; improved CTR 14% QoQ.

Fix: Use keywords in achievement bullets with proof.

11) Ambiguous dates and timelines Inconsistent formats break field mapping.

Before: Jan '21–Now, 2023/7–Present After: Jan 2021–Present (use one format consistently) Fix: Standardize to MMM YYYY–MMM YYYY or Month YYYY–Present.

D) Structural Mistakes

12) Non-standard section headings Creative labels confuse parsers.

Before: "My Journey", "Wins & Lessons", "Academic Path" After: "Professional Summary", "Work Experience", "Education" Fix: Use conventional headings throughout.

13) Unclear job hierarchy (title/company/dates) Parsers struggle when titles and companies are merged.

Before

Data Analyst at BrightCo, Istanbul 2022–2026 Built dashboards...

After

BrightCo — Istanbul (Jan 2022 – May 2026)
Data Analyst
• Built dashboards...

Fix: Put company on one line, title on the next, and dates clearly.

E) Technical Mistakes

14) Exotic fonts, emoji, special bullets Non-standard glyphs can render as boxes or disappear.

Before: Script fonts, emoji bullets, decorative arrows After: System fonts (11–12 pt), standard bullets (•) Fix: Stick to common fonts (e.g., Calibri, Arial, Cambria) and plain bullets.

15) Mobile-unfriendly layout Tiny font, cramped margins, and long unbroken URLs hurt readability.

Before: 9pt text, 0.3" margins, long raw URLs breaking lines After: 11–12pt body, 1" margins, readable links and spacing Fix: Test on a phone. Ensure line length, spacing, and links are tap-friendly.

ATS Parsing Test Methods

Use these quick checks before every submission:

1) 90-Second Plain-Text Test

2) Keyword Coverage Check

  1. From the JD, list 10 must-have terms.
  2. Ctrl/Cmd-F each term in your résumé.
  3. If missing (and true to your experience), add it to a bullet or the summary. → How to extract keywords step-by-step: how to extract ATS keywords

3) Tokenization Peek (local)

# Save your resume as resume.txt first (export to plain text)
tr -cs '[:alnum:]+/#.-' '
' < resume.txt | tr '[:upper:]' '[:lower:]' \
| sed -E '/^(and|the|with|for|to|of|in|a|an|or|on|by|be|as|at)$/d' \
| awk '{count[$0]++} END {for (w in count) print count[w], w}' \
| sort -nr | head -30

Goal: Confirm the top tokens are skills and domain terms, not junk characters.

4) Reading-Order Sanity (Python)

text = open("resume.txt").read().lower()
sections = ["summary","skills","experience","education","certifications"]
print(all(text.find(sections[i]) < text.find(sections[i+1]) for i in range(len(sections)-1)))

True indicates sections appear in a clean sequence.

5) Mobile Check

Prevention Checklist

Real-World Mini Case Studies

Case Study 1 — Two-Column Designer CV Failing Autofill

Case Study 2 — Scanned PDF for Senior Analyst

Case Study 3 — Ambiguous Dates & Fancy Bullets

FAQ

Q1: Is a two-column résumé ever safe for ATS? It can work only if the structure is simple and the plain-text order remains intact. For online applications, single column is the safer default. See the comparison: single column vs two column

Q2: Should I submit DOCX or PDF? If a posting doesn't specify, a text-based PDF is the safe default: every mainstream ATS accepts it and it renders identically for the human reader. Send DOCX when the posting explicitly asks for a Word document. Either way, confirm you can select the text.

Q3: Where should I put keywords? In your summary, skills, and experience bullets—with measurable outcomes. Learn extraction methods: how to extract ATS keywords

Q4: Can I use icons or a headshot? Avoid graphics in the résumé body; they don't help parsing or searchability and can increase file size.

Q5: What's the best section order? For most roles: Summary → Skills → Experience → Education → Certifications. If new to ATS, read: what an ATS-friendly resume is

Q6: How do I know my layout is mobile-friendly? Open the file on your phone and check font size, line wrapping, and tap-friendly links. Keep body text 11–12pt.

Check your own file before you apply. Upload your resume for a free basic structure check — no account needed. It reports whether your headings, dates and contact block parse cleanly, which is the part you cannot see by looking at the page.

Conclusion & CTA

Avoiding ATS pitfalls comes down to clean structure, clear language, and simple exports. Use a single-column, text-first layout with standard headings and consistent dates. Integrate role-specific keywords into achievement bullets, then run the plain-text, keyword, and mobile tests before you submit. For deeper dives, see our comprehensive resources:

Building and previewing a resume on ForgeMyCV is free and needs no account; a PDF download starts at $0.99. Start with a template, or check the file you already have first.