Job portals and HR systems reject resumes more often than most people realize — often silently, with a generic error message that gives no hint of what actually went wrong. The problem is almost always a file size issue, a format issue, or a combination of both. Here's what to check before you submit.

The format question: PDF vs Word

PDF is almost always the safer choice for resume uploads. A PDF displays identically regardless of which device, operating system, or version of Word opens it — the layout, fonts, and spacing you designed are preserved exactly. A .docx file may reflow when opened in a different version of Word, LibreOffice, or Google Docs, potentially scrambling your carefully designed layout.

The exception: some older ATS (Applicant Tracking Systems) parse text out of your resume to store it in their database, and a few older systems handle .docx better than PDF for that purpose. If the form specifically says "preferred format: Word" or ".docx," follow that instruction. Otherwise, default to PDF.

File size limits are lower than you'd expect

Most job portals cap resume uploads at 1–5 MB. A standard text-and-formatting resume PDF should be well under 500 KB. If yours is larger, something has gone wrong:

ATS-friendliness and file format

ATS software reads your resume to extract name, contact info, skills, and work history. Some things break this process:

Quick pre-upload checklist

Resume PDF too large? Compress it here →