Here's how to choose the right file format for your resume

These are the best fonts to use on your resume, according to designers
These are the best fonts to use on your resume, according to designers

Deciding what type of file format to submit your resume in is a decision usually made at the last minute — or not at all.

But recruiters agree it's more important than job seekers think. Submitting your resume in the wrong file format could make it appear distorted or, worse, unreadable to hiring managers — effectively ruining your chances of securing a new job.

CNBC Make It spoke with multiple recruiters who agreed there are a few rules every applicant should follow.

Don't use obscure formats including .txt, .rtf, .pages or even .docx, as not everyone has the newest version of Microsoft Word. Using one of these formats could result in a hiring manager not being able to open or read your resume, says Allyson Goodman, CEO and co-founder of the Pyramid Consulting Group.

Never scan your resume into your computer using a printer, scanner or fax machine, says Brie Reynolds, senior career specialist at FlexJobs. She calls this a "fatal mistake," in part because the low quality image file makes your resume difficult to read.

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With those scenarios eliminated the question remains: Should you send your resume as a PDF or a doc?

Submitting your resume as a PDF is (almost always) your best bet

If you're submitting to a small company or directly to a person via email, a PDF is the way to go.

Submitting your resume as a doc doesn't guarantee your resume will look the same way it does to you. If you're using a unique font or complicated formatting, for example, your resume may look totally different when opened on another person's computer.

"We like a PDF version, as it formats the resume nicer," Goodman says.

If you're sending your application through a company application website, the answer is a bit more complicated.

Many recruiters rely on something called an "ATS," which stands for applicant tracking system. Many large and mid-size companies use them to ingest hundreds of applications in an easy-to-review format for hiring managers.

Why one page is the right length for your resume
Why one page is the right length for your resume

These systems often rank submissions by the number of keyword matches the system finds. For example, a resume for a computer programmer position that included the words "computer programming, Java and HTML" would rank more highly than resumes without those terms. To rank applicants, the software needs to "read" your resume, or extract the text from it.

Until recently, some ATS systems weren't able to read text from PDF files. This has made the doc format the longtime favorite choice, says Carolyn Thompson, executive recruiter and Managing Principal at Merito Group. Thompson encourages job applicants to submit their resume as a doc just to be safe.

But others argue that in today's digital age, sending your resume by PDF is fine, so long as it doesn't contain images or other "non-traditional" formatting.

If applying through a company website, avoid complicated formatting

"Most applicant tracking systems have evolved to the point where both file types are equally readable, so long as the information is structured in a legible format," says Proven Recruiting CEO and co-founder Louis Song. "This wasn't the case two to three years ago, but AI and machine learning have significantly improved recruiting software capabilities."

But Song notes that a few things remain unreadable, including "tables, headers, graphics or multi-column formatting."

Your resume should highlight this one key trait
Your resume should highlight this one key trait

If you decide to submit your resume as PDF, make sure it's saved in a standard resume format and is "readable," meaning a system can rip the text from it. To ensure that yours is readable, simply check if you can highlight lines of text from it. If you can, you're all set. If you can't, an ATS system won't be able to read it.

Go back to your original resume file, save it as a doc and then save it as a PDF.

Tailor your format to the recipient

If you're worried that that the company you're applying to may have an older ATS system, then you can play it safe.

"When in doubt, submit a doc file to applicant tracking systems and a PDF to recruiters," Reynolds says.

This ensures your information gets scanned properly in a tracking system and at the same time looks exactly the way you'd like it to when being reviewed by an actual human.

Or on the other hand, if you've used a unique font or want to make sure other details of your resume appear to your hiring manager exactly as they do to you, you can go with a PDF file. Just make sure you don't have any images or multiple columns, which could throw off the resume-reading software.

"If you're applying online," Song says, "it's best to play it safe and prioritize the accessibility of your information over an interesting design."

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Here are the most creative resumes we've ever seen
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