PDF vs Word: When to Use Each Format

Use Word while a document is still being written or changed, and use PDF once it's finished and needs to look the same for everyone who opens it. That single rule settles most of these decisions. Word is a working format built for editing, so it reflows text depending on the fonts, printer drivers, and version installed on whoever's machine opens it. PDF is a delivery format built to freeze a page exactly as you laid it out. Draft in one, deliver in the other. Below is the detail: when each format genuinely wins, which is more accessible than people assume, which survives ten years in a folder, and what you actually lose converting back and forth.

What's the Actual Difference Between PDF and Word?

They solve different problems, and the naming hides that. A Word file (.docx) describes a document as content plus instructions: this paragraph is Heading 1, this text is bold, wrap it at whatever width the window is. Your computer then renders that using the fonts and settings it happens to have. A PDF describes a page as a finished picture: this character sits at these exact coordinates, in this embedded font, at this size.

That single design choice explains almost every practical difference:

Worth knowing that PDF isn't an Adobe product any more. It's an open ISO standard, ISO 32000, and the PDF Association, which serves as ISO's committee manager for the PDF standards, describes ISO 32000-2 (PDF 2.0) as the culmination of roughly nine years of work by about 30 subject-matter experts. Since 5 April 2023 the full specification has been available at no cost, where previously it was purchase-only. DOCX is standardised too, as Office Open XML, but it's far more tied to one vendor's implementation in practice.

When Should You Send a PDF?

Send a PDF whenever the document is finished and the layout matters. Specifically:

• Anything going to a client or customer. Quotes, invoices, proposals, reports. You control exactly what they see.
• Anything being signed. PDFs support digital signatures natively, and a signed PDF carries evidence of tampering if anyone alters it afterwards.
• Anything that must not be edited. Contracts, certificates, official statements, price lists.
• Anything with careful design. Brochures, menus, CVs, anything where a shifted line break ruins the page.
• Anything going to someone whose software you don't know. Every phone, tablet, and browser opens a PDF. Not everyone has Word.
• Anything you're keeping for years. More on that below.

The unglamorous reason PDF wins so often: you know what the other person will see. A Word document that looks perfect on your laptop can arrive with different fonts, a spilled table, and an extra blank page. That doesn't happen with PDF.

When Should You Send a Word File?

Word earns its place whenever the document isn't finished, or the recipient's job is to change it.

• Collaborative drafting. Tracked changes, comments, and version history are genuinely good, and PDF has no real equivalent.
• Templates other people will fill in. A Word template someone customises beats a PDF form for anything complex.
• When the recipient asks for it. Recruitment agencies often want Word CVs because they edit your contact details before forwarding. Publishers want Word manuscripts. Just send what's asked for.
• Long documents that get read on phones. Word reflows to the screen width. A PDF makes people pinch and zoom.
• Content that will be reused. If chunks of this document will end up somewhere else, keep it editable.

The mistake here is sending a Word file as the final deliverable out of habit. If nobody is going to edit it, there's no upside and several downsides.

Which Format Is More Accessible?

This is the part most PDF vs Word comparisons skip, and the honest answer probably isn't what you'd guess. A properly structured Word document is usually more accessible than an average PDF, and HTML beats both.

The UK's Government Digital Service made the case bluntly: information published in a PDF is harder to find, use and maintain than the same information in HTML. At the time of writing they were hosting around 200,000 PDFs and publishing tens of thousands of new ones every month, which is why the problem mattered enough to write about. Their specific complaints are worth knowing because they apply to your documents too. PDFs open in a new window or app and break the user's context. They don't reflow, so magnifying the text means scrolling sideways. They're rarely updated once published, so they go stale and accumulate broken links.

The accessibility point is sharper still. GDS cited a 2016 assistive technology survey finding that screen magnifiers and screen readers are the most commonly used assistive technologies, and those are precisely the tools PDFs cause the most trouble for.

The US federal position has landed in the same place. Section508.gov states plainly that PDFs are often not the most accessible or mobile-friendly option and that federal policy now requires agencies to prioritise HTML formats, using PDFs only when necessary. The UK's guidance on publishing accessible documents says HTML should be your first choice whenever possible.

None of that makes PDF unusable. It means a PDF is only accessible if someone made it accessible: proper tags, a reading order, alt text on images, real text rather than a scan. Our PDF accessibility guide walks through what that involves, and the W3C's PDF techniques for WCAG is the reference implementers use.

Do Accessibility Rules Actually Apply to Your Documents?

For a lot of people, yes, and the rules name PDF and Word specifically rather than talking vaguely about websites. If you work for or with a US state or local government, this is now a legal obligation with a date on it.

The Department of Justice published a final rule under Title II of the Americans with Disabilities Act on 24 April 2024, setting WCAG 2.1 Level AA as the technical standard for web content and mobile apps provided by state and local government entities. The part that matters here is scope. The rule covers what it calls conventional electronic documents, and it lists them: PDFs, word processor file formats, presentation file formats, and spreadsheet file formats. Posting a PDF instead of a web page doesn't put you outside the rule.

The deadlines moved recently, so check the current ones rather than a guide written in 2024. In April 2026 the Department published an interim final rule extending compliance by a year. Per ADA.gov's first-steps guidance, entities with a population of 50,000 or more now have until 26 April 2027, and entities under 50,000 or any special district government have until 26 April 2028.

Two exceptions are worth knowing because they narrow the job considerably. Preexisting conventional electronic documents get an exception if they were posted before the compliance date and aren't currently used to access services, programs, or activities. And individualized, password-protected documents about a specific person, property, or account, think a tax bill or a utility statement, don't have to meet WCAG 2.1 either.

If you're outside US government work, none of this binds you. But it's a fair signal of where the expectation is heading, and the practical advice doesn't change: publish reference content as HTML, and if you do ship a PDF, tag it properly.

Which One Survives Long-Term Storage?

PDF, and it's not close. There's a whole ISO standard for exactly this: PDF/A, defined in ISO 19005, whose stated purpose is to preserve a document's static visual appearance over time, independent of the tools and systems used to create, store, or render it.

PDF/A does that by refusing the things that rot. Fonts must be embedded rather than referenced, so the document can't change when a font disappears. External dependencies, JavaScript, and encryption are excluded. The file has to carry enough metadata to describe itself. The family has grown alongside the core standard: PDF/A-1 was built on PDF 1.4, PDF/A-2 on PDF 1.7 as formalised in ISO 32000-1, and PDF/A-4 on ISO 32000-2:2020, which is PDF 2.0.

A .docx has no equivalent. It's tied to a specific application's rendering behaviour, and open it in fifteen years on whatever Word has become and the layout may well have drifted. That's why archives and records offices standardise on PDF/A. The UK's National Archives publishes format guidance for official publications on exactly these grounds.

So for anything you need to still be readable and unchanged years from now, export PDF and keep the Word original alongside it if you might need to edit again.

Does Converting Between Them Lose Anything?

The two directions are not remotely equal, and this trips people up constantly.

Word to PDF is clean. You're taking a document with structure and rendering it to a fixed page. Everything you had is preserved or improved: fonts embed, layout locks, headings can carry through as bookmarks and tags. Use the built-in Export or Save As PDF rather than printing to PDF, because printing usually discards the structure that makes the file accessible.

PDF to Word is reconstruction. You're asking software to look at fixed characters on a page and guess what the paragraphs, tables, and styles were. It's genuinely hard, and results vary with the document. Simple text converts well. Multi-column layouts, complex tables, and heavy design usually need cleanup afterwards. And if the PDF is a scan, there's no text at all until OCR runs, and OCR makes mistakes.

The practical takeaway: keep your editable original. Converting a PDF back to Word is a recovery operation, not a workflow. Our PDF to Word guide covers how to get the best result when you have no choice, and the PDF to text guide is often the better route if you only need the words.

Which Format Should You Use for Common Jobs?

The quick lookup:

On the resume question specifically, our sister site has a fuller answer alongside a free builder at IWantFreeResume.com, including how applicant tracking systems actually parse each format.

What Mistakes Should You Avoid?

Six errors account for most of the trouble:

• Sending Word as the final deliverable. If nobody's editing it, you've handed over an editable file with your layout at the mercy of their machine.
• Losing the editable original. Keep the .docx. Converting the PDF back later is a downgrade every time.
• Printing to PDF instead of exporting. Printing flattens the structure, which strips out the tags that make a PDF accessible and searchable.
• Assuming a PDF is accessible because it's a PDF. It isn't unless someone tagged it. A scanned PDF is an image of a document, not a document.
• Using PDF for content that should be a web page. Both the UK and US governments have moved away from this for good reasons.
• Forgetting the metadata. Word stores author names, comments, and revision history, and exporting to PDF can carry some of it across. Check the document properties before you send anything sensitive.

That last one catches people out more than it should. If a file is going outside your organisation, look at what's in the properties first. Our guide to password protecting a PDF free covers the other half of sending documents safely, and the digital signature guide explains how signing works once you've committed to PDF.

What Do People Ask About PDF vs Word?

Should you send a resume as PDF or Word?

Send a PDF unless the job ad or recruiter asks for Word. A PDF looks identical on every machine, so your layout survives. Some recruitment agencies want Word because they edit your details before passing it on, and a few older applicant tracking systems parse Word more reliably. When the posting names a format, use that one.

Is PDF or Word better for legal documents?

PDF, almost always. It fixes the layout, so pagination and clause numbering can't shift, and it supports digital signatures and password protection. Word is for the drafting stage, where tracked changes and comments matter. Draft in Word, then issue and archive the final version as PDF.

Can you edit a PDF like a Word document?

Not really, and that's the point. A PDF stores where each character sits on the page rather than a flowing document, so editing means nudging fixed elements. You can fill forms, annotate, and make small text fixes, but heavy rewriting means converting to Word first, editing there, and exporting a fresh PDF.

Which format is smaller, PDF or Word?

It depends on the content. For text-heavy documents the two land close together. For anything image-heavy, a PDF is usually smaller because it compresses images on export, while Word often stores them near full size. A PDF also compresses further without much visible loss, which Word files don't do well.

Is PDF more accessible than Word?

No. A well-structured Word file is usually more accessible than an average PDF, and HTML beats both. The UK Government Digital Service found PDFs are harder to find, use and maintain, and cause the most trouble for the screen readers and magnifiers people actually rely on. PDFs can be accessible, but only if properly tagged.

Sources: UK Government Digital Service, "Why GOV.UK content should be published in HTML and not PDF," 16 July 2018 (gds.blog.gov.uk); GOV.UK guidance on publishing accessible documents (gov.uk); US General Services Administration, Section508.gov, on creating accessible PDFs (section508.gov); US Department of Justice, final rule on the accessibility of web content and mobile apps provided by state and local governments under ADA Title II, published 24 April 2024, and ADA.gov first-steps guidance reflecting the April 2026 interim final rule that extended compliance to 26 April 2027 and 26 April 2028 (ada.gov); The National Archives guidance on accessibility and alternative formats (nationalarchives.gov.uk); W3C PDF techniques for WCAG (w3.org); PDF Association on ISO 32000-2 and the ISO 19005 PDF/A family (pdfa.org). All linked above.

Got a PDF you need to shrink before emailing it? Our free PDF compressor runs in your browser, and the compression guide explains how much you can realistically save.