Playground

Try the Kernstra PDF viewer and editor with your own PDF.

Drop a file or pick one below. It opens in a new tab, in the real Web SDK, a JavaScript PDF viewer and editor, with its default configuration, and it never leaves your browser.

Drop a PDF here

Any size. Scans, forms, signed files, password-protected files.

Choose a fileNothing uploadsOpens in a new tabGone when you close it

Or open one of ours

Each one shows something specific.

Q3 board pack32 pages · 18.9 MBEdit a figure in the table Services agreement14 pages · 1.2 MBSign page 14 Patient intake form4 pages · 380 KBFill, flatten, download Aircraft technical log100 pages · 107 MBOpens before it downloads Scanned lease9 pages · 6.4 MBHighlight a scan Multilingual brochure6 pages · 2.1 MBEdit RTL and CJK text

What opens

A new tab, the real viewer, your file.

01Every tool, default configuration

The build your users would get. Text editing, markup, signing and forms on.

02Handed over in memory

From this page to the new tab inside your browser. Never written to disk, never sent.

03Close the tab and it is gone

Download the edited copy first if you want it. No history, no account.

kernstra.com/playground/open

KernstraPlaygroundyour-file.pdf2.4 MB · in this tab's memoryEditedWeb SDK 1.0.0ConfigureDownload

SelectPanAdd textEdit textHighlightDrawShapesEraseSignMarksImageNoteText boxPagesSearch

Pages

Try this1Click the Q3 revenue figure and change it. The font, size and alignment stay.2Undo, then zoom to 400%. The text is still text.3Place a signature and download the edited copy.Document upload · none

Same code in your app

Everything you just did is three lines away.

The playground is the Web SDK with its defaults. Install it, pass a key, and open a document.

01Install

One package, TypeScript types included, ES2022.

npm install @kernstra/pdf-web-sdk

02Initialize with your key

Development keys are free and work on localhost for as long as you like.

await Kernstra.init({ license: 'krn_dev_…' });

03Open a document

The defaults are what the playground runs. Pass a config object to change them.

new PDFViewer(container, doc);

Get started Read the docs

Questions

Before you drop something confidential

Can I use a real, confidential file?

Yes. The file is handed to the new tab inside your browser and rendered from memory. It is not uploaded, cached, or logged. Close the tab and it is gone. The security page shows the one request the viewer makes.

Why does the playground open the PDF in a new tab?

The viewer gets the whole window and this page stays light. The two tabs talk only inside your browser, and closing the viewer tab leaves nothing behind.

Is there a file size limit in the playground?

No. A file you drop is read from your disk, so there is nothing to download, and only the pages on screen are drawn. A 107 MB scanned file opens in under a second on a laptop.

Can I open a password-protected PDF?

Yes. You will be asked for the password in the viewer. It is used in memory to open the file and never stored.

Does it work on a phone?

Yes. Open this page on your phone and drop a file from Files or Drive; the viewer opens in a new tab there too. The toolbar folds into a bottom bar and text editing works with touch.