Merge PDF
AvailableMerge PDF files locally in your browser and download one combined document.
Merge PDF
AvailableNothing to show yet
—
Add at least two PDF files. They will be merged in the order shown above.
Validated locally: file type, size and browser support are checked before anything runs
Preparing your file
Reading the file locally and checking that its type and size match what this tool expects. Nothing has been uploaded.
Converting locally
PDF assembly uses pdf-lib; page rendering runs locally with PDF.js.
- Read
- Validate
- Convert
- Package
You can leave this tab open in the background — the conversion keeps running on your device, and progress is reported when you come back.
Conversion complete
Your converted file is ready to download.
Nothing to show yet
—
Nothing to show yet
—
Output format
PDF
Duration
—
Processed
On your device
Size change
—
The converted file was assembled in your browser and is released when you leave or reset this page
Something went wrong
The conversion could not be completed. Nothing was uploaded, and no partial file was saved.
This conversion is not supported yet
Your file passed every local check, and this is exactly where the PDF toolkit engine takes over. It does not implement this particular input and output pair yet, so nothing was converted and no download was offered.
| Engine | PDF toolkit |
|---|---|
| Frontend module | static/engines/pdf-engine.js |
| Extra downloads | None — this tool runs on browser APIs alone |
| Runs in a worker | No — the browser is fast enough here |
| Processing | On your device |
This page is the integration point. When the engine lands, it is loaded here and the same six states drive the real conversion.
No upload for supported tools — the file is processed by this browser
Up to 100 MB
About this converter
Merge PDF files locally in your browser and download one combined document.
What happens to your file
For supported tools the file is read with the browser File API and held in memory on your device. It is validated, processed by the PDF toolkit engine in a Web Worker, and the result is handed back as a download. At no point is the file sent to a server.
What to expect from the output
The tool writes PDF. Formats differ in what they can represent, so expect simple structure to transfer reliably while detailed layout may be simplified by the target format.
How to use this converter
Four steps, none of which involve an account.
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1 Choose your file
Drop a pdf file onto the drop area or browse for it.
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2 Check the output
The output format is preselected as PDF. Change it if the tool supports other targets.
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3 Convert
Everything happens on your device, so speed depends on your machine rather than a queue.
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4 Download
Save the result, then reset the tool to clear it from memory and start again.
Conversion states
Design referenceThese are the six states the workspace moves through. The live tool above uses the same markup; this panel shows each one side by side so the behaviour can be reviewed without converting anything.
1 Empty — no file chosen
2 File selected — ready to convert
- PDF example.pdf
3 Preparing — reading locally
Preparing your file
Checking the file type and size. Nothing has been uploaded.
4 Converting — progress reported
Converting locally
- Read
- Validate
- Convert
- Package
Runs in a Web Worker so the page stays responsive.
5 Completed — result ready
Conversion complete
Your converted file is ready to download.
# Release notes
- Faster image conversion
- **New:** Markdown to PDF
- Fixed line ending detection
release-notes.md
Release notes
Faster image conversion
New: Markdown to PDF
Fixed line ending detection
release-notes.html
Output format
PDF
Duration
—
Processed
On your device
Size change
—
Interface preview
This is the completed state as designed. No file was converted and the download action is disabled, because the conversion engine for this tool has not been connected yet.
The converted file was assembled in your browser and is released when you leave or reset this page
6 Error — recoverable
That file could not be read
The file appears to be damaged or its contents do not match the
.pdf extension. Nothing was uploaded.
Try again
Choose a different file
Frequently asked questions
Answers specific to Merge PDF.
Is this tool free?
Yes. Merge PDF is free to use and needs no account, no sign-up and no email address.
Where is my file processed?
This tool is being built for local processing, so the file is handled by your own browser. Until that engine is connected the page shows an explicit notice instead of pretending the conversion succeeded.
Which files can I use as input?
Accepted formats are PDF. The converter writes PDF.
Can I convert a scanned PDF to text?
Text extraction works on PDFs that already contain a text layer. Scanned pages need optical character recognition, which is a separate tool planned for a later phase.
Is there a page limit for merging?
There is no fixed page limit. The practical ceiling is your device's memory, since the document is assembled in the browser.
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