April 22nd, 2026
If you sell digital books, sheet music, sewing patterns, design templates, or any kind of PDF‑based product, you’ve probably been told or have come to understand that “piracy is inevitable.” It’s true that once something is on the internet it can be copied, but you can still tilt the odds in your favor. You can watermark and password your files, customizing them on-the-fly using plugins like PDF Ink. You can also easily add metadata and digital signatures to a PDF. But what else can you do? But one surprisingly effective—and often overlooked—technique is embedding an invisible watermark on a handful of unpredictable pages. That’s easy to do using PDF Ink out-of-the-box, with settings included in […]
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January 29th, 2026
If you run a WooCommerce shop that sells digital goodies like e‑books, manuals, or templates in PDF format, you already know how satisfying it is to watch a customer click “Download.” Imagine taking that moment a step further: each PDF leaves the checkout with a tiny, personalized imprint—perhaps their name and email, order number, copyright notice, or timestamp—right on (or hidden inside) the file. Not only does this add a professional touch, it helps you prove ownership, deter piracy, and keep tidy records. PDF Ink allows for adding quite a bit of customer data easily using magic tags. There is no magic tag for VAT, but using a little code, we can and add a […]
December 3rd, 2025
When you pair SetaPDF‑Stamper with PDF Ink, a whole new world of “smart PDFs” opens up. Imagine every external link inside a downloadable PDF guide instantly morphing into a personalized gateway—complete with affiliate codes, UTM tags, or a secret user token—without ever touching the original source file. With just a few lines of PHP, you can walk the document’s page tree, sniff out each PDF UriAction, and splice a custom query string onto the URL. We'll show you how.
October 5th, 2025
WooCommerce order numbers often appear inconsistent due to WordPress's auto-increment ID system. Sequential numbering plugins create a proxy mapping for clean, consecutive order numbers. PDF Ink takes this further by allowing easy watermarking with dynamic tags like [ORDERNUMBER], enabling shops to generate professionally branded, personalized downloadable PDFs with minimal effort.
July 8th, 2025
If you are trying to upload EPUB to WordPress or sell EPUB files or other ebooks using WooCommerce, you might have come across one obscure little problem: WP doesn’t support EPUB by default. You might be having trouble uploading EPUB files to your WP Media Library with a “This file cannot be processed by the web server” error message, and/or you might run into the “Invalid download link” error screen when you try to download your WooCommerce EPUB. These error messages simply mean that WordPress does not enable this file/media type (MIME type) by default, or the file type has been turned off by a security plugin (or your hosting provider). Keep reading to learn […]
May 5th, 2025
Sometimes we’ll handle a deluge of files for a single project—contracts, spreadsheets, presentations, licenses, and source data—all floating around in different emails, shared drives, or chat threads. What if all of that could live in one self-contained PDF “package?” This isn’t just a hypothetical. File stream embedding, an advanced PDF feature, allows businesses to create intelligent, all-in-one digital containers. This approach streamlines workflows, enhances branding and brand loyalty, enhances compliance, and ensures data integrity. PDF Ink and SetaPDF-Stamper can be used in PHP-based web applications to add embedded streams conditionally and dynamically, making these tasks magical and almost… fun. Each PDF download can be customized programmatically for the file, purpose, and/or end user — without […]
March 12th, 2025
A case study showing how to get a customer's WooCommerce order information printed on their PDF during download, to discourage file sharing & theft. In this case, we have a sheet music distributor who wishes to stamp the purchasing choir name on each page.
November 13th, 2023
Here is some PHP code for WordPress/WooCommerce which will make PDF Ink recognize TWO custom shortcodes in any watermark content: [VARIATION_DESC] and [VARIATION_NAME]. These translate to variation description and variation name, both aspects of a WooCommerce variable product. This code (everything above the dashed line) should get added anywhere in your functions.php file. If unsure where to put it, add it at the end of the file. You could also add the snippet using the WordPress plugin called “CODE SNIPPETS” (front and back end). This snippet development was sponsored by customer Michael. Thanks Michael! For reference (maybe for people migrating from WaterWoo to PDF Ink) here is a snippet which would have worked with WaterWoo:
October 27th, 2023
When choosing between WooCommerce PDF Watermark and PDF Ink for watermarking and passwording PDFs, both plugins offer essential features but differ significantly. PDF Ink provides greater flexibility with customizable watermarks, allowing HTML tags, custom fonts, and multiple watermark locations. It supports advanced encryption options like AES and offers robust file management, including recycling previously watermarked PDFs. In contrast, WooCommerce PDF Watermark has limitations, such as fewer customization options and higher pricing. Read the full comparison!
April 17th, 2023
A customer wrote with a neato request last month. If one WooCommerce product had several PDFs, and wasn’t a variable product, how could each PDF in the list be watermarked differently from the others? There is no setting for that inside PDF Ink because WooCommerce hasn’t exactly made that function easily possible, and also because it somehow hadn’t been requested until last month. That’s sort of amazing considering how long the plugin has been around! Anyway, it was a good request and so we added a filter hook called ‘pdfink_woo_filter_settings‘. (This hook replaces the ‘wwpdf_filter_settings_array’ in WaterWoo PDF Premium, with identical arguments.) Filtering Settings Because WooCommerce — unlike Easy Digital Downloads — doesn’t give a […]
February 15th, 2021
There are quite a few built in shortcodes, but sometimes we just need something… special. You can add your own shortcodes to PDF Ink for on-the-fly customized watermarks on PDF pages. In this simple example we are going to create a shortcode to reflect a customer’s order total (price) in the watermark, when using a custom shortcode: [TOTAL_PRICE] Now when you use [TOTAL_PRICE] in your watermark, the PDF will show the total price of the WooCommerce order the PDF was purchased in. Perhaps this way you could print out the price on a gift certificate. More on how to create gift certificates using PDF Ink can be found here. Another Example In the following example […]
July 7th, 2020
Clear communication about password-protected PDFs is crucial to avoid customer confusion. For WooCommerce shops, customize the Thank You page and order confirmation emails to inform customers of their PDF passwords. Use hooks to add messages indicating that passwords are their email addresses or phone numbers. Highlight this information with bold text or colors to ensure it stands out. Effective communication enhances the customer experience, reduces support inquiries, and builds trust, ultimately leading to repeat business and positive word-of-mouth for your shop.
June 1st, 2020
This is a bit more of a technical post for PDF Ink users who would like to add dynamic customer or order data to file watermarks–data that isn’t already covered in existing PDF Ink “Magic Tags.” There are already magic tags for order number, purchase date, quantity Purchased, customer name, address, phone, email, etc. etc. But maybe your project requires pulling a different tidbit from the customer profile or order data. If that’s the case, keep reading. Your project will likely involve writing a few lines of code. These days you can probably present the question to AI and have it write a PHP snippet for you. If you would rather have human help, or […]
October 6th, 2018
Here is an example of adding new magic tags to PDF Ink for on-the-fly and totally-customized watermarks. A Brazilian customer using WooCommerce requested a magic tag to display the Cadastro de Pessoas Físicas (CPF) on PDFs. CPF is a taxpayer identification number all citizens of Brazil must use to shop online within Brasil. In order to collect CPF data from customers, our customer uses the Woocommerce Extra Checkout Fields for Brazil plugin.* We wrote the following code to programmatically create the magic tag [BILLING_CPF]. This magic tag will import any customer’s CPF number into their personalized PDF during stamping (when the customer clicks download). The “WooCommerce Extra Checkout” plugin mentioned above must be in use, […]