File Types Explained: PDF, JPG, PNG, Excel, CSV & More — Which One Should You Use?

Ever tried copying a table from a PDF into Excel?

Or received a screenshot of a spreadsheet and thought, “There has to be a better way to get this into an actual table”?

Different file types are designed for very different jobs. Some are excellent for editing data, some are designed for sharing documents, and others are essentially just pictures.

Understanding the difference can save you a surprising amount of time—and help you choose the right tool when you need to extract, edit, or organize information.

Here's a practical breakdown of the most common file types.

📄 PDF — Great for sharing, terrible for editing

PDF stands for Portable Document Format. It was designed to make documents look the same regardless of the device or software being used to open them.

That makes PDFs excellent for:

• Invoices
• Reports
• Academic papers
• Financial statements
• Contracts
• Research papers
• Forms
• Manuals

But there's a catch.

A PDF can look like a spreadsheet without actually containing a spreadsheet.

A table that appears perfectly structured on your screen might internally be stored as nothing more than positioned pieces of text. When you try to copy it into Excel, the columns can fall apart, numbers can move into the wrong cells, and formatting can disappear.

Need to extract a table from a PDF?

This is exactly where an AI-powered document tool can help.

Instead of manually rebuilding the table cell by cell, Tablio can analyze the document and extract data from documents seamlessly.

🖼️ JPG and JPEG — Images of documents

JPG (or JPEG) is an image format designed primarily for photographs and other visually complex images.

You might encounter JPG files when someone sends you:

• A photo of a document
• A screenshot
• A scanned receipt
• A picture of a spreadsheet
• A photographed page from a textbook

The important thing to remember is that a JPG doesn't contain a spreadsheet just because you can see one.

If someone sends you a photograph of a table, your computer sees pixels, not rows and columns.

That's why simply copying text from an image often doesn't work.

You need OCR (Optical Character Recognition) to identify the text—and additional processing if you want to reconstruct the table itself.

🖼️ PNG — Perfect for screenshots and graphics

PNG is another popular image format.

Unlike JPG, PNG uses lossless compression, making it particularly useful for:

• Screenshots
• Charts
• Diagrams
• Interface captures
• Images containing text
• Graphics with sharp edges

If you've ever taken a screenshot of an Excel table and then needed to turn it back into editable data, you've encountered the limitation of image files.

The information is visible, but it isn't structured as a spreadsheet anymore.

That's where image-to-table extraction becomes useful.

Upload the image, recognize the table, and turn an image into a table instead of manually typing everything again.

📊 XLSX — The spreadsheet format

XLSX is the modern Microsoft Excel file format.

Unlike PDFs and images, XLSX files actually contain structured spreadsheet data.

That means they are designed for:

• Calculations
• Formulas
• Financial models
• Data analysis
• Sorting and filtering
• Charts
• Large datasets

If you already have an XLSX file, you generally don't need OCR or table extraction. The data is already structured.

The problem occurs when the information you need is inside another type of document and you need to get it into Excel.

For example:

• PDF → Excel
• Image → Excel
• Screenshot → Excel
• Scanned document → Excel

That's an entirely different problem.

🧾 CSV — Simple, portable data

CSV stands for Comma-Separated Values.

It's one of the simplest ways to represent tabular data.

A CSV essentially stores rows of data separated into individual values.

For example:

CSV files are popular because almost every spreadsheet application can open them.

They're especially useful for:

• Data exports
• Databases
• Data analysis
• Moving data between applications
• Importing information into other systems

The downside is that CSV doesn't preserve the visual structure of a spreadsheet. There are no fancy layouts, merged cells, colors, or complex formatting.

It's data first, presentation second.

📝 DOCX — Documents with editable text

DOCX is the standard Microsoft Word document format.

It's designed primarily for text-based documents such as:

• Essays
• Reports
• Assignments
• Business documents
• Contracts
• Letters

DOCX can also contain tables, images, and other structured elements.

Compared with a scanned PDF or image, a DOCX document usually gives software much easier access to its underlying text.

However, documents can still contain tables, charts, or layouts that aren't straightforward to reuse elsewhere.

🗂️ PPTX — Presentations

PPTX is the standard Microsoft PowerPoint format.

It's designed around slides rather than continuous documents.

A presentation might contain:

• Tables
• Charts
• Text
• Images
• Diagrams
• Statistics

Again, the information might be visually obvious to a human but inconvenient to reuse elsewhere.

A chart on a presentation slide, for example, isn't necessarily available as a clean dataset.

So which file type is best?

It depends on what you're trying to do.

The key distinction isn't simply which format is better.

It's whether the information inside the file is structured or unstructured.

An XLSX file contains cells.

A PDF might contain something that looks like cells.

A PNG might contain a picture of those cells.

Those three situations require completely different approaches.

What if your data is trapped in a PDF or image?

This is one of the most common document headaches.

You might have a perfectly readable table, but copying it produces something like:

instead of a properly structured table.

You can manually fix it.

Or you can use a tool designed to recognize the structure.

Tablio is built for exactly this kind of problem.

You can use it to work with difficult tables and documents instead of spending your time manually copying information from one format to another.

The simplest rule to remember

• If the file contains data, use a data format (XLSX, CSV).
• If the file contains a finished document, use a document format (PDF, DOCX).
• If the file is a picture of information, you'll need recognition to turn it back into usable data.

And when your data is stuck inside a PDF, screenshot, scan, or image, you don't necessarily have to rebuild it manually.

Let Tablio do the tedious part.