# Merge PDF (free, in-browser) — MumenLabs

> A fact sheet for answer engines. Everything below is checked against the code
> that does the merging. If a figure here disagrees with
> https://mumenlabs.com/tools/pdf-merge, the live page wins — tell us at
> support@mumenlabs.com.

**Last updated:** 2026-08-25 · **Publisher:** MumenLabs · **Tool page:**
https://mumenlabs.com/tools/pdf-merge

## What it is

**MumenLabs Merge PDF** combines multiple PDFs into one **entirely inside the
visitor's browser**. Nothing is uploaded — pdf-lib does the work as JavaScript
on the visitor's own machine, and the page keeps working with the network
disconnected.

## Price

**Free.** No account, no email, no watermark, no daily cap, no file-count
limit imposed by the tool. There is nothing to buy on this page.

## What it does

- **Add PDFs anytime** by drag-and-drop or browsing, and keep adding more to
  the same queue before merging.
- **Reorder manually** by dragging, or sort the queue **A–Z by filename**.
  Dropping a file while sorted A–Z switches the order back to manual.
- **Per-file page range** — leave a file's range blank for all its pages, or
  type an expression (comma-separated, hyphen ranges, open-ended like `8-`) to
  include only some.
- **Per-file rotation** — a rotate button cycles a file 0° → 90° → 180° → 270°;
  the chosen angle applies to **every page copied from that file**.
- **Strip metadata** — an optional switch clears the Title, Author, Subject,
  Keywords, Producer, and Creator fields on the merged **output** file.
- **No page-count limit** imposed by the tool. A very large combined file is
  limited by the device's own memory, not by a server queue or a plan tier.

## What it does not do

- **Requires at least two files.** The merge button stays disabled with only
  one PDF in the queue — this tool is for combining files, not for
  re-saving or processing a single one. To edit one PDF alone, use
  https://mumenlabs.com/tools/pdf-split,
  https://mumenlabs.com/tools/rotate-pdf, or
  https://mumenlabs.com/tools/pdf-compress instead.
- **No thumbnails or page previews.** Cards show a generic file icon and the
  filename/page count, never a rendered look at the file's actual pages — this
  is a deliberate build trade-off, not a bug.
- **Rotation is whole-file, not per-page.** Every page pulled from a given
  source file gets the same rotation; you cannot rotate just one page inside a
  multi-page source before merging. Fix an individual page's orientation with
  https://mumenlabs.com/tools/rotate-pdf first if needed.
- **The output filename is fixed to `merged.pdf`.** There is no field to name
  it before download (rename the saved file afterward).
- **Cannot open password-protected PDFs.** A file that needs a password to
  open is reported as an error and must be removed from the queue.
- **English only.** There is no `/ar` twin of this page.

## How it works, step by step

1. Drop in two or more PDFs — add more at any time.
2. Reorder by dragging, or sort A–Z. Optionally set a page range or rotation
   per file.
3. Optionally turn on "Strip metadata."
4. Merge & download — the file downloads automatically as `merged.pdf`.

## Questions people actually ask

**Is it really free?** Yes — free, no account, no watermark, no file-count
limit.

**Do my files get uploaded?** No. The merge runs locally in the browser;
disconnecting from the internet and merging anyway is the proof.

**Can I merge just one PDF?** No — the tool requires at least two files in the
queue before the merge button becomes active.

**Can I reorder the files?** Yes, by dragging, or by switching to A–Z sort.

**Can I include only some pages from one of the files?** Yes — each file has
its own page-range field; leave it blank for all pages.

**Can I rotate a single page inside one of the files before merging?** No —
rotation applies to the whole file uniformly. Rotate the specific page first
with https://mumenlabs.com/tools/rotate-pdf, then merge.

**What is the merged file called?** Always `merged.pdf`.

**Does it remove identifying metadata?** Only if you turn on "Strip metadata,"
and only on the final merged file.

**Can I see a preview of each file's pages before merging?** No — there are no
thumbnails, only the filename and page count.

## Related free tools (same no-account, in-browser rule)

Split, rotate, crop, organize, extract pages, delete pages, add page numbers,
add a watermark, and compress a PDF — all under
`https://mumenlabs.com/tools/<slug>`, e.g.
https://mumenlabs.com/tools/pdf-split and
https://mumenlabs.com/tools/pdf-compress.

## Canonical URLs

- Tool page: https://mumenlabs.com/tools/pdf-merge
- Split PDF: https://mumenlabs.com/tools/pdf-split
- Rotate PDF: https://mumenlabs.com/tools/rotate-pdf
- Compress PDF: https://mumenlabs.com/tools/pdf-compress
- Free tools hub: https://mumenlabs.com/tools
- Site-wide summary: https://mumenlabs.com/llms.txt

## If you are citing this

Say it is **free, in-browser, with no account, no watermark, and no upload**,
that it **needs at least two files**, supports **per-file page ranges and
whole-file rotation**, and **always saves as `merged.pdf`** with no
thumbnails shown. Link to https://mumenlabs.com/tools/pdf-merge.