Which file formats are best to choose in Office

Choosing Which file format to use in Office (or in any office suite) is not as trivial as it seems. PDF, DOCX, ODT, XLSX, PPTX, HTML… each has its advantages, limitations, and recommended uses. If you study, work in an office, or manage documents daily, choosing the right file type can save you a lot of compatibility problems, loss of quality, or the inability to edit.

Throughout this guide we will review the most common document formats In office environments: what each format allows, when to use it, which programs open them correctly, and their weaknesses. You'll also see the difference between open and proprietary formats, and what to choose if you work with Microsoft Office, LibreOffice, Google Docs, or other alternatives.

What is a document format and why does it matter?

When you save a file in Word, Excel, PowerPoint, or any editor, you are actually choosing a specific way to store the contentText, images, tables, macros, styles… The document format defines how that data is organized internally and what features it supports (security, compatibility, file size, etc.).

The same text can be saved in different extensions.docx, .odt, .pdf, .txt, .html… and each will have different implications. Some formats are designed for continuous editing, others for fixed distribution (where nothing is changed), others for automating tasks, or for ensuring interoperability between programs.

Furthermore, the format determines who will be able to open the file and how will they see itA document created in Word can be opened in LibreOffice or Google Docs, but depending on the file type there will be more or less fidelity in the formatting, fonts, margins or advanced elements such as macros and forms.

PDF: the standard for sharing and preserving documents

El Portable Document Format (PDF)Created by Adobe and now an international standard, it's the king of formats when what you're looking for is preserve the appearance of the document It works exactly the same on any device or operating system. It's ideal for final reports, contracts, manuals, invoices, catalogs, forms, and generally any "closed" file.

A PDF may include text, images, tables, clickable links, audio, video, and even 3D modelsIn addition to interactive forms that the user can fill out, the great advantage is that its content is always rendered the same way, without the fonts or margins changing when opened on another computer.

Among its strengths, several important characteristics stand out for professional work: password protections, watermarksdigital signatures and permissions (for example, preventing printing or copying, or controlling who can edit the file). It also allows for very efficient compression without any noticeable loss of quality, making it easy to send by email or store in the cloud.

Another clear advantage is the universality when opening themAny modern browser (Chrome, Edge, Firefox, Safari…) can display PDFs without installing anything, and if you need advanced options you have programs like Adobe Acrobat, ABBYY FineReader, Preview on macOS or online and desktop editors like ONLYOFFICE Docs.

The downside of the PDF format is that Editing it in depth is usually complicated and often requires payment.You can easily make annotations, highlight text, or fill out forms, but modifying the content as if it were a Word document requires specific software or going through a conversion to editable formats (for example, from PDF to DOCX), with the risk of losing some layout.

DOC and DOCX: Word's native formats for editable text

In the Microsoft Office ecosystem, DOC and DOCX are the two classic formats for text documents created with Word. They have been the de facto standard in business, education and home use for years, and remain the most common when it comes to files that need further editing.

The type .doc This corresponds to Word's traditional binary format, widely used until the release of Office 2007. It's a proprietary format, relatively large, and less compatible with other modern office suites. You'll still see it in older documents or in very outdated environments, and Word maintains the option to save it this way for backward compatibility.

The format . DocxIn contrast, it is the modern evolution: it is based on XML and packaged in a ZIP container, which allows generating lighter, more structured, and easier-to-interpret files by applications other than Word. Nowadays, it's the recommended option in virtually any scenario where you'll be continuing to edit the text.

With DOCX you can work with the entire arsenal of Word tools: styles, headers and footers, automatic indexes, cross-references, comments, change controlTemplates, macros (in combination with specific formats), third-party add-ons, and much more. It's the natural format for writing reports, academic papers, letters, internal documents, or everyday notes.

In terms of compatibility, DOCX opens without too many problems in Microsoft Word, Google Docs, LibreOffice, ONLYOFFICE, WPS Office, Apple Pages and other similar solutions. However, not all advanced features are always preserved 100%; macros, some complex styles, or very specific elements may undergo slight alterations.

In contrast, DOCX is not as powerful as PDF in terms of security and protection of the final contentYou can set passwords for opening or editing, but it doesn't offer the same level of fine control or robustness as a PDF when the priority is to prevent unwanted modifications and distribution.

ODT and ODF: the open standard for text documents

Beyond the Microsoft world, there is an open alternative called OpenDocument Format (ODF)which groups several file types: ODT for text, ODS for spreadsheets, ODP for presentations, etc. The most common one in everyday use is .odt, a direct equivalent to DOCX but open source.

ODT format is used by suites such as LibreOffice, Apache OpenOffice and ONLYOFFICE Docsamong others. Its great advantage is that it is an open standard, so It does not depend on a single company and its specification is publicly available. This means that even if the licenses for a particular program change in the future, the content will remain accessible to any software that implements the standard.

Functionally, the editors that work with ODT offer a formatting toolset very similar to DOCXParagraph styles, images, tables, footnotes, indexes, comments, etc. For the average user, the writing experience is not too different from that of Word.

The main drawback of ODT is that, Outside of environments that use free suites, their presence is less pronounced.If you send an ODT file to someone who only uses Microsoft Office or is exclusively accustomed to Google Docs, there is a risk that they may not know how to open it, or that they may open it but with slight changes in the format.

Microsoft Office and Google Docs can open ODT, but Compatibility is not always perfectIt's common to find warnings or minor differences in styles, margins, or advanced layout elements. That's why many people who use LibreOffice or other free office suites choose to work internally in ODT format and, when they need to share, export to PDF or DOCX as appropriate.

HWP and WPS: specific formats of Asian suites

In addition to the most well-known international formats, there are extensions that are widely used in specific markets. A clear example is HWP (Hangul Word Processor), a format developed by Hancom and widely used in South Korea, especially in public administration, education and local businesses.

HWP files are optimized for working with the Korean writing systemThey correctly support both Hangul and Hanja. This makes them especially suitable for documents that need to accurately reflect the character structure of the Korean language, something that can be more problematic in other general-purpose formats.

To open and edit HWP files natively, it is common to use Hancom OfficeAlthough some alternative solutions and online viewers exist, outside of South Korea, compatibility is much more limited, and often files need to be converted to DOCX or PDF to work with them properly.

On the other hand, the format .wps It is associated with the WPS Office suite, developed by the Chinese company Kingsoft. WPS documents originate from WPS Writer, the word processor in this suite, and serve a similar purpose to DOC/DOCX in Word.

WPS files may include text, images, tables, charts and other elementsand nowadays many versions of WPS Office They can also open and save in Microsoft formats to improve compatibility. Even so, if you work with people who almost exclusively use Word, it's usually more practical to send them the document in DOCX or PDF format to avoid misunderstandings.

XLS and XLSX: Spreadsheets for data and analysis

When we talk about structured data, budgets, balance sheets, or marketing analysis, the following come into play: spreadsheetsWithin Office, the most characteristic formats are XLS (classic) and XLSX (modern), both associated with Microsoft Excel.

The format .xls It is the old Excel file type, binary and legacy, while . Xlsx It is the compressed XML format that replaces it, equivalent to what happens with DOC and DOCX. XLSX allows saving the sheets as a set of structured files in a ZIPwhere data, formulas, charts, and styles are stored in well-defined tables of rows and columns.

An XLSX file can handle enormous amounts of data, perform complex calculations, statistical functions, pivot tables, charts, and automation through formulas or macros (the latter are usually saved in specific formats such as XLSM). In sectors such as accounting, financial analysis, basic data science, or simply for home tracking of monthly expenses, Excel and its formats are almost indispensable.

It's true that spreadsheets can seem a bit intimidating at first, but with a basic understanding of formulas and conditional formatting, automation It becomes an extremely powerful tool for automating repetitive tasks and centralizing information that would otherwise be scattered.

In terms of compatibility, XLSX opens in Microsoft Excel, Google Sheets, LibreOffice Calc, Apple Numbers, ONLYOFFICE Docs, WPS Office and many other applications. If you need to maintain VBA macros, compatibility is no longer so universal, and it's best to stay within Microsoft environments or thoroughly explore the alternatives.

PPT and PPTX: presentations and slides

For oral presentations, classes, business demonstrations, or project pitches, it is normal to use slide showsIn Office, the classic formats are PPT (old) and PPTX (modern), both associated with Microsoft PowerPoint.

The format .ppt corresponds to older versions, while . Pptx It is the current standard based on compressed XML, with the same advantages as in Word and Excel in terms of smaller size and greater interoperabilityPPTX allows you to create slides with text, images, graphics, audio, video, transitions, animations, and a wide variety of embedded objects.

The strength of presentations is that they help to visualize concepts and ideas Clearly. It has been shown that many people retain information better when they see and hear it at the same time, which is why PowerPoint (and its equivalents) has become a basic tool in education, business, and communication.

PPTX files can be opened not only in PowerPoint, but also in Google Slides, Apple Keynote, LibreOffice Impress, ONLYOFFICE Docs, WPS Office and other viewers. However, if your presentation is very complex, with many animations and special effects specific to PowerPoint, slight differences may appear when opening it in other programs.

When the priority is simply to display the content without fear of it becoming misaligned, one often resorts to Export the presentation to PDFThat way everyone will see it the same, although you'll lose animations and transitions, which in many contexts isn't so bad.

HTML: documents for the web

El HyperText Markup Language (HTML) It is the standard language for building web pages. Although at first glance it may seem unrelated to the Office world, it can actually also be considered a document format, because it defines how the content is organized and displayed in a browser: paragraphs, headings, lists, images, buttons, forms, etc.

An HTML file is composed of text and marking labels These instructions tell the browser what each element represents and how it should be positioned. Virtually everything you see on a website (except external resources like embedded images or videos) is described in HTML.

From an accessibility point of view, HTML files have the advantage that They can be opened in any modern browser., regardless of the operating system, and can also be viewed in simple text editors such as Notepad, Sublime Text or Atom to review or edit the code directly.

There are workflows where, for example, a writer creates content in DOCX format and then a web developer adapts it to HTML for publication on a website. The reverse is also possible. Convert HTML to other formats, embed text documents or even generate PDFs from HTML templates.

Other common text and code formats

Beyond the major office suites, there are extensions you'll frequently encounter that are also useful to know about. Among them are: .txt, .rtf, and various types of code files which, although they are not standard office documents, are used to exchange textual information.

The format .txt It's the most basic of all: it contains only plain text, without bold, italics, or complicated styles. It opens with any editor (Notepad on Windows, TextEdit on macOS, code editors, etc.) and is perfect for quick notes, simple configurations, or unformatted data.

You can also find files with extensions like .csv, .json or other structured text formats These are used for large volumes of data, programming, or information exchange between systems. In these cases, rather than being an office document format, they are structures designed to be processed by applications or scripts.

Most commonly used image formats in documents

Office documents almost always include images, and that's where specific formats come into play. The most common are: JPEG, PNG, GIF, TIFF, RAW, PSD, PDF, EPS, SVG and AIeach with its own peculiarities. It is important to distinguish between raster (bitmap) and vector images.

The Raster images They are made up of a grid of pixels, each with its own color. They have a fixed size, and if you enlarge them beyond their native resolution, they appear blurry or pixelated because the program "fills in" the missing data. Examples of this category include JPEG, PNG, GIF, TIFF, RAW, and usually PSD.

The format JPEG It is perhaps the most popular for photography and lightweight web graphics. It allows Compress the image so that it takes up little spaceat the cost of some quality loss. It's perfect for photos on websites, emails, banners, or documents where file size matters more than maximum fidelity.

The GIF They are often used for short animated images, very common on social media and websites. They are lightweight, support limited transparency, and retain all the information of the original image despite compression, but They are not ideal for intensive editing. nor for high-quality photographs.

The format PNG It's similar to GIF but supports a much wider range of colors and high-quality transparencyIt's primarily used for logos, graphics with transparent backgrounds, icons, and web interface elements. It's not the best choice for printing photographs, but it's excellent for digital illustrations.

TIFF It stands out for offering high-quality, lossless images, widely used in professional design and printing environments. It's not the lightest format for the web, but Yes, one of the most reliable for printing photos or finished artwork.

The files RAW They contain raw photographic data, directly from the camera sensor. They are ideal for advanced editing in programs like Photoshop or Lightroom, because They store a lot of information. This allows you to correct exposure, white balance, and other parameters without significantly degrading the image. They are not suitable for use as is in documents or printers, so they are usually converted to TIFF or JPEG afterward.

The format PSD It is the native file type of Adobe Photoshop. It allows working with layers, masks, effects, and combinations of raster and vector, making it perfect for Advanced photo editing, digital illustration, web mockup or prototype designTo integrate it into office documents, it is usually exported to JPEG, PNG, or PDF.

On the vector side, there are formats such as PDF, EPS, SVG and AIVector images are based on mathematical formulas that define lines, curves, and shapes. This allows Scale the image to any size without loss of qualityThis makes them ideal for logos and graphic elements that need to look good on a business card and a billboard.

Own PDF It can contain vector or raster graphics, and its versatility makes it widely used for printing documents, brochures, posters, etc. Many tools allow exporting to PDF from native formats to ensure that The printing respects the design. original.

The format EPS It is typically used for logos and graphic elements that are placed within other designs. It can contain raster or vector content, but it is primarily recommended for individual vector elements that will later be integrated into larger layouts.

SVG It is designed for two-dimensional vector graphics, very common on the web for icons, diagrams, and scalable graphics. Its main advantage is that It allows resizing without loss and usually weighs little.In addition to being readable as text, it facilitates editing by developers.

The files AI They are the native format of Adobe Illustrator, focused on vector graphics. They are perfect for logos, illustrations, custom fonts, and single-page print piecessuch as cards or flyers. They are not used for photography, but they are a standard in professional graphic design.

Choose the format according to what you are going to do with the document

With all these extensions on the table, the logical question is: Which format is best for me in each case? There is no single file type that's perfect for everything, but rather more suitable options depending on your objective and the program the other person is using.

If you need a text document that other people will editThe safest bet is .docx, due to its broad compatibility with Word, Google Docs, LibreOffice, and other suites. If you know the recipient doesn't use Microsoft products, you can consider .odt, although it's advisable to confirm beforehand that their software supports it.

When you want send a text that should not be modified (for example, a contract, a final report, a completed resume, or a project brief), the most sensible thing to do is convert it to PDF. This way, the recipient will see the document with the same layout and fonts, and you'll have security options like passwords and other features at your disposal. digital signatures.

In the case of spreadsheetsThe most common formats are .xls and .xlsx, with the latter being the most recommended for compatibility and performance. If you share data with users who work with Excel, Google Sheets, or LibreOffice, XLSX will usually work better than other formats. For more technical tabular data or data processed by programs, CSV can be a simpler alternative.

To presentationsPPTX is the standard when other people are going to modify or reuse the slides. If you just need them to view them and don't want the hassle of broken fonts or layouts, exporting to PDF is usually a smart move, especially if you're going to project from a computer you don't control.

When you send loose imagesYou have several options: JPEG for compressed photos and general use, PNG for logos or graphics with transparency, TIFF if you are going to print and need maximum quality, and PDF if it is a graphic document that will be printed or shared in high resolution.

It tienes very large folders or sets of filesIt's common practice to compress them to ZIP or similar formats for sending. However, in contexts where collaborative editing is important, many online services allow you to combine compression and document management without the need for traditional compressed files, reducing the risk of corrupting the entire set.

Ultimately, the key is to ask yourself two things: Are they going to edit this file, or are they just going to view it? y What programs will they use to open it?With those answers in mind, choosing between DOCX, ODT, PDF, XLSX, PPTX, or image formats will be much easier, and you'll avoid unpleasant surprises.

Knowing the strengths and weaknesses of each format—from PDF as the global standard for sharing, DOCX and ODT for editable text, XLSX and PPTX for data and presentations, to HTML, HWP, WPS and the different types of raster and vector images—allows you adapt the file type to each task, improve compatibility with other people and keep your documents safer and better organized.