Google’s HR department sees a ton of job candidates, sometimes as many as 50,000 a week.

They see a lot of great resumes and a lot of bad ones. What bothers HR head Laszlo Bock is that so many good candidates cheat themselves out of a potential job by committing a deadly sin on their resume.

Bock recently took to LinkedIn to share a few of the most common resume mistakes he sees while fishing through the ocean of candidates looking to break into the GooglePlex.

We gleaned these five pieces of valuable insight from his post:

Proofread your resume NOW

Seriously, stop right now and proofread. We’ll wait. Better yet, have someone else help you look for mistakes.

According to Bock, over half of all resumes currently include a typo. It’s not headline news that a good resume should be free of these kinds of errors, but grammar and punctuation is about more than showing off your language arts chops.

Your resume is often the first real peek a prospective employer gets at your personality and your focus on detail. Don’t ruin their first impression with a simple error.

Your Resume Needs Less Length and More Focus

Bock suggests one resume page for every 10 years of work experience. But it’s his follow-up point that should really hit home for job-seekers.

The purpose of a resume is not to earn you a job. The purpose of a resume is to earn you an interview.

Don’t use your resume as a comprehensive statement of who you are. Use your resume to magnify your key strengths and help you stand out from the crowd. Trust your interview skills to bring home the job.

PDF Your Resume

There’s nothing wrong with Microsoft Word or Google Docs, but resume formatting can get all jumbled up when files move across different platforms.

No, it’s not your fault that your interviewer’s 10-year-old PC won’t open your beautiful new resume, but it will affect your career just the same.

Save yourself some hassle by turning your resume into a PDF file. That way it will look exactly as you intended on any computer.

If Your Resume Can’t Keep a Secret, Neither Can You

You may think that you can mention confidential client work in your resume, because your former client will never see it…

You’d be right, but your prospective employer will be reading your resume. If you don’t respect the confidentiality of your former colleagues, the prospective employer will assume you are not trustworthy.

Bock offers a helpful tip here. Don’t put anything on your resume that you’d be upset reading on the front page of the New York Times.

Resume Lies are Career Poison

The New York Times rule also works well here.

Lying on a resume will almost always come back to bite you. In today’s job market, it’s not just the big lies that hurt. Something as simple as inflating the amount of time you spent with a company or rounding up your GPA can sink your chances at a great job.

Hiring managers have powerful tools to find out who you are and who you were. They can be surprisingly understanding, but they can’t do much with a dishonest candidate. Keep it classy and give yourself the best chance for long-term success.