Axiomatic ToolsFree Fast Essential

Merge PDF files

Combine multiple PDFs into one — instant, in your browser.

  • PDF & Office
  • Free to use
  • Runs in your browser
Use via API

Add your files

0 of 2

Set your options

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Run Merge PDF

Private by default. Runs entirely in your browser — files never uploaded.

Add 2 files above to run this tool.

Report a bug

Three steps

How to use Merge PDF

  1. Step 01

    Pick your input

    Drag in 2 application/pdf files, or drop a single ZIP holding them.

  2. Step 02

    Configure & run

    Adjust the options (add bookmarks, order) and click Run. We try the in-browser path first, falling back to our servers for large files.

  3. Step 03

    Download the result

    A single application/pdf is downloadable below the form.

When run in the browser, your file never leaves your device. When the server path is used, files are encrypted at rest and deleted an hour after upload — 24 hours if you are signed in.

About merge pdf

Combine PDF files into one — runs in your browser, no upload needed. It sits in the pdf & office shelf alongside 83 other pdf & office tools, needs no account, and keeps the same behaviour whether you open it here or call it through the REST API.

It takes PDF files and gives back PDF. It runs over a whole batch in one go. Large files stay on your machine, so size is bounded by your own memory rather than an upload limit. The work happens in your browser, so the file is never uploaded and the tool keeps working offline. The same operation is available programmatically at POST /v1/pdf/merge.

Merge PDF questions

Are my files uploaded?

No. Merge runs entirely in your browser via WebAssembly.

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