Question 1

Are PDFStack tools really free?

Accepted Answer

Yes — every tool on PDFStack is free to use with no hidden costs, no signup, no email required, and no daily caps. Tools run in your browser so there are no server costs to recoup.

Question 2

Does PDFStack upload my files?

Accepted Answer

No. PDFStack processes all files entirely in your browser using JavaScript libraries (pdf-lib and PDF.js). Your documents never leave your device, which makes PDFStack genuinely private — unlike most online PDF tools that upload files to a server.

Question 3

What PDF tools are included?

Accepted Answer

PDFStack includes 30+ tools: merge PDF, split PDF, compress PDF, PDF to Word, PDF to PowerPoint, PDF to Excel, Word to PDF, PowerPoint to PDF, Excel to PDF, edit PDF, edit Word, edit PowerPoint, PDF to JPG, JPG to PDF, sign PDF, watermark, rotate PDF, HTML to PDF, unlock PDF, protect PDF, organize PDF, PDF to PDF/A, repair PDF, add page numbers, scan to PDF, OCR PDF, compare PDF, redact PDF, crop PDF, AI summarizer, and translate PDF.

Question 4

Can PDFStack edit Word and PowerPoint files?

Accepted Answer

Yes. PDFStack includes browser-based editors for both .docx Word documents and .pptx PowerPoint presentations alongside its PDF tools — no Microsoft Office required.

Question 5

Do I need to install anything?

Accepted Answer

No installation, no extension, no download required. PDFStack runs entirely in any modern web browser (Chrome, Firefox, Safari, Edge) on Windows, macOS, Linux, iOS, and Android.

Question 6

Is PDFStack safe to use for confidential documents?

Accepted Answer

Yes. Because PDFStack runs locally in your browser and never uploads files, it's well-suited for confidential documents like contracts, medical records, financial statements, and personal IDs. Nothing is sent to a server.

Question 7

Is there a file size limit?

Accepted Answer

There's no server-imposed limit because PDFStack doesn't use a server. The practical limit is your device's available memory — most modern devices handle PDFs well over 100MB.

Question 8

Does PDFStack work offline?

Accepted Answer

Once the page is loaded in your browser, most tools continue to work even if your internet drops, because all processing happens locally. Refreshing the page does require a network connection to load assets.

Every PDF tool.
Right here.

Choose your tool

Create a workflow

PDFStack helps you work with PDFs, Word files, and PowerPoint decks in one browser app.

Every PDF tool.Right here.

Choose your tool

Create a workflow

PDFStack helps you work with PDFs, Word files, and PowerPoint decks in one browser app.

Every PDF tool.
Right here.