AI PDF Studio Pro: free online, no upload
PDF Studio Pro bundles the Stirling-PDF-class operations people reach for most often into one free, browser-based workbench: stamp a watermark across every page, add running page numbers, edit the title/author/subject/keywords metadata, turn a batch of images into a single PDF, or export PDF pages back out as PNG images. Every operation runs on pdf-lib inside your own browser tab, so the document itself is never uploaded or stored on a server — which makes it safe for contracts, transcripts, invoices and other sensitive paperwork.
How to use AI PDF Studio Pro
- Drop in your PDF: Open PDF Studio Pro and drop a PDF (or a set of images) onto the page. It loads in a few seconds and runs inside your browser tab.
- Pick an operation: Choose watermark, page numbers, metadata editing, images-to-PDF or PDF-to-PNG from the tabs. Nothing is uploaded to any server.
- Adjust and preview: Set the text, position, colour or page range and check the live preview until it is exactly what you need.
- Download the result: Download the finished PDF or image. You can repeat it as many times as you like, free.
Key features
- Text watermark with custom position, size, colour and opacity
- Running page numbers (top/bottom, left/centre/right, custom start number)
- Edit Title, Author, Subject, Keywords, Creator and Producer metadata
- Images (JPG/PNG) to PDF, and PDF pages to PNG, in either direction
- 100% private: processed with pdf-lib in your browser, nothing is uploaded
Popular uses
- Stamp "CONFIDENTIAL" or a company watermark across a contract before sharing it
- Add page numbers to a thesis, report or legal brief
- Clean up or correct the author/title metadata before publishing a PDF
- Combine scanned receipts or ID photos into a single PDF, or export pages as images
Frequently asked questions
Is PDF Studio Pro really free?
Yes. There are no credits, watermarks on the output or paid plans. Online Free Tools is a free welfare project funded only by ads.
Are my PDFs uploaded to a server?
No. PDF Studio Pro parses and rewrites the PDF entirely inside your browser tab, so the file never leaves your device.
Can I add a watermark and page numbers at the same time?
Yes. Each operation (watermark, page numbers, metadata edit, image/PDF conversion) can be applied one after another to the same working file before you download it.
Is there a file size or page limit?
No account-based limit is enforced. Because everything runs locally, the practical ceiling is your device's memory — typical multi-page contracts, reports and forms work instantly.
Does PDF Studio Pro work offline?
Yes. Once the page has loaded, watermarking, page numbering, metadata editing and image/PDF conversion keep working without an internet connection.
Does it work on mobile?
Yes. It works in Chrome, Safari, Edge and Firefox on Android, iPhone, Windows and Mac.
Built with open-source technology: Hopding/pdf-lib.
No subscriptions. No payments. Ever. Full power is unlocked by inviting friends, never by paying.
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