What is PDF?
A plain-English definition, and the tools that work with it.
A PDF (Portable Document Format) is a file type that preserves a document's exact layout (fonts, images and formatting) so it looks identical on any device or printer. It's the standard for sharing finished documents like reports, contracts, invoices and resumes.
- PDFs are fixed-layout: unlike a Word file, they won't reflow or shift between apps, which is why they're used for anything final.
- A PDF can hold real, selectable text (exported from a document) or just an image of text (a scan): the latter needs OCR to become searchable.
- You can compress, merge, split, sign, protect and convert PDFs without special software. It all runs in a modern browser.
Tools for PDF
Free, private and in your browser. No sign-up.
Compress PDF
Shrink a PDF's file size right in your browser. Pick a compression level, see exactly how much you saved, and download. No uploads, no watermark.
PDF Editor
Edit a PDF in your browser: add text, draw, highlight, drop in a signature, and rearrange or rotate pages, then export. Free, private, no uploads.
Merge PDF
Combine multiple PDF files into a single document, drag to set the order, then download. Free, fast and entirely in your browser.
PDF to Word
Turn a PDF into an editable Microsoft Word (.docx) document, text extracted into clean, editable paragraphs, entirely in your browser with no upload.
PDF problems we solve
Hit one of these? Here's the fix.
- My PDF is too largeUpload limits are usually 2MB, 5MB or 10MB. The steps to get any PDF safely under the line without wrecking the quality.
- I need to edit the text in a PDFYou don't need expensive software to change a word or fill in a form. Edit the PDF in place and download the updated file.
- I need to turn a PDF into an editable Word documentNeed to reuse the text or make big changes? Convert the PDF to Word, edit in a familiar app, and convert back if you need a PDF again.
Frequently asked questions
Related terms
- OCROCR (Optical Character Recognition) is technology that reads the text inside an image or scanned document and turns it into real, selectable, searchable text. It's what makes a photo of a page copyable instead of just a picture.
- JSONJSON (JavaScript Object Notation) is a lightweight, text-based format for structured data, built from key–value pairs and lists. It's the standard way apps and APIs exchange data because it's easy for both humans and machines to read.
Keep exploring
Problems we solve
Definitions
From the blog
- How to Add Page Numbers to a PDF: Positions, Formats, and Ranges Explained
- How to Extract Text from a PDF (Including Scanned Ones with OCR)
- How to Add a Watermark to a PDF: Text and Image Watermarks Done Right
- Turn Phone Photos into a Scanned PDF
- How to Convert Markdown to PDF: Turn Plain Text Into a Polished Document
Common tasks
Try Compress PDF
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