Can I merge password-protected PDFs?

No — folio cannot unlock encrypted PDFs in this version. Unlock each PDF in a separate tool first, then drop the unlocked copies into the merger.

Will bookmarks and form fields survive merging?

Page content, annotations and most form fields copy across cleanly. Cross-document bookmarks (TOC links pointing into another file) don't survive because they're tied to the original document's structure.

How many PDFs can I merge at once?

Up to 20 files per batch, each up to 100 MB. The merged document's practical size is limited by your browser's memory.

Is this PDF toolkit free?

Yes. folio is free to use, no account is required, and there are no paid plans.

Are my PDFs uploaded to a server?

No. folio runs entirely in your browser. Your PDFs are never uploaded, never seen by our infrastructure, and never stored anywhere outside your device. When you close the tab, every file is gone.

Which operations are supported?

Merge PDFs, split a PDF into ranges, compress a PDF, convert PDF pages to JPG or PNG, build a PDF from images, rotate all or selected pages, add a watermark, and extract plain text. All of this happens in your browser.

Is there a file size limit?

Yes. Each file may be up to 100 MB. Browser memory is the real ceiling — very large scanned PDFs may struggle on lower-end devices.

Can I work with multiple PDFs at once?

Yes. Merge and Images→PDF accept up to 20 files in a single batch. Split, Compress, Rotate, Watermark and Extract Text take one PDF at a time.

Will my converted images / PDFs lose quality?

Compress and PDF→JPG/PNG re-render pages at the DPI/quality you pick, so there is a small generational loss like any image re-encode. Merge, Split, Rotate, Watermark and Extract Text do not re-render — they only edit the existing PDF objects, so quality is preserved.

Can folio open password-protected PDFs?

Not yet. If your PDF requires a password to open, please unlock it first in a dedicated app. We deliberately skip password handling to keep folio fully client-side and free of legal grey areas.

Not in this version. Extract Text only works for PDFs that already have selectable text. Scanned image-only PDFs need OCR, which is a separate, much heavier project we may add later.

Why does the first PDF→Image take a moment?

When you first use an operation that renders PDF pages (PDF→JPG, PDF→PNG, or split previews), folio downloads the rendering engine (~1 MB). After that it stays cached and subsequent operations start immediately.

Are ads required to use the tool?

No. Ads are isolated from the converter. The tool works completely even if ads fail to load or are blocked.

Multiple PDFs → One PDF

Merge PDFs into one

Drop two or more PDFs below and folio stitches them into a single document — entirely in your browser. Nothing is uploaded; everything is erased when you close the tab.

Drop your PDFs here

Pick up to 20 PDFs to merge into a single document

Choose PDFs

PDF

Upload a file to start.

Max 20 PDFs, 100 MB each.

Every operation runs entirely in your browser. Your files never leave your device.

About Merge PDFs

Why merge PDFs locally?

Sending invoices, contracts, scans and reports through a third-party merger means uploading sensitive documents to a stranger's server. folio runs pdf-lib inside your browser, so your files never leave your device — there's no temp storage, no cache, no log of what you merged.

How big can the merge be?

You can combine up to 20 PDFs at once, each up to 100 MB. The merged file inherits the smaller of pdf-lib's defaults and your browser's memory ceiling — most laptops handle a few hundred pages comfortably.

Are bookmarks and form fields preserved?

Page content, annotations and most form fields copy across cleanly. Cross-document bookmarks (table-of-contents links pointing into a separate file) won't survive — they're tied to the original document's structure.

About this operation

PDF → PDF

What it does

Drop two or more PDFs and folio stitches them into a single document with pdf-lib running inside your browser. The merge preserves page content, most annotations and most form fields. Cross-document bookmarks (table-of-contents links pointing into a separate file) do not survive because they are bound to the original document's structure. Up to 20 PDFs per batch, each up to 100 MB; the merged file inherits your browser's memory ceiling.

When to use it

Combine scanned receipts into one invoice file
Stitch multiple chapter exports into a single report
Bundle signed contracts before sharing
Reorder a multi-PDF deliverable into one document

Limitations — what it doesn't do

Cannot unlock password-protected PDFs — unlock each file first
Cross-document bookmarks (TOC links pointing to other files) are dropped
Interactive form fields with conflicting IDs may collide
Up to 20 files per batch, 100 MB per file

Every tool runs entirely in your browser.

Frequently asked questions

Your PDFs never leave your device

folio is a static page. Every operation runs inside your browser via pdf-lib (edit) and pdfjs (render). There is no server-side processing, no upload, no temporary file, no cache. When you close this tab, every file is gone.

No account required.
No server processing. Your PDFs stay on your device.
No caching, no Service Worker, no IndexedDB persistence.
pdfjs-dist (lazy-loaded for rendering) is fetched from your own origin; nothing else is sent.