Local PDF tool - browser processing

Add text to a PDF without uploading

Use Add Text when you need to label, correct, annotate, or fill visible blanks on a PDF while keeping the source file on this device.

Add text locally See the proof

0 bytes sent proof

What the widget measures

The panel counts what leaves your browser after you choose a file. The site's own scripts and fonts load like any web page — what you will never see is a request carrying your PDF. Check it here, or open your browser's Network tab and see for yourself.

0 bytes of your document sentStarts measuring when you choose a file on a tool page

Document request bodies: 0 bytes
App network after file open: 0 bytes
Processing engine: Browser WASM worker

The number is scoped to request bodies after you choose a document. App assets such as JavaScript, WASM, and fonts can still load; those are not your PDF bytes.

Verify it yourself

Open DevTools, then the Network tab.
Choose a PDF in the tool and complete the action.
Filter for fetch or XHR requests; document processing should not create a request carrying your file.

Stronger check: load the tool page first, then disconnect from the network before choosing the file. Already-loaded tool code can continue processing locally, but a first visit still needs the site assets.

Steps

How to do it in Lemmafour

Choose Add text locally.
Use Choose PDF or LOAD PDF to open the file.
Select Add Text in the toolbar.
Click the page where the new text should appear.
Set font size, color, and placement in the task controls, then Export.

Expert note

Added text is not the same as editing existing text

Adding text creates new PDF content on top of the page. It is useful for visible corrections, labels, and filled blanks, but it does not remove the original text underneath. If the old content is sensitive or wrong in a way that must not remain extractable, use secure redaction instead of covering it with new text.

FAQ

Questions people ask before using this tool

Can I add text to a scanned PDF?

Yes, as a visible overlay. The tool does not recognize or replace scanned text; it places new PDF text on the page.

Can I change the color and size?

Yes. The editor includes style controls for new text before export.

Does added text remain selectable?

The export writes PDF text where supported, so it can usually be selected by PDF readers.

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