A watermark is text or an image printed behind document text. Watermarks are transparent, so the text that is in front of watermarks is visible. Some of the most commonly used are “Draft” or “Paid”. Other examples are a logo printed lightly behind a letter or the word "Confidential" printed lightly on a contract.

With Smart PDF Converter, you can select text or an image as a watermark. You can set the level of transparency, an angle of rotation, scale and the exact position of a watermark. You can set a watermark to appear on every page of a document or only on selected pages, to be visible only in print or only on your computer display, and to be on top or behind the text. You can also apply a watermark to multiple documents at once.

How to insert watermarks

Click Insert Watermarks on the Tools tab. A new window will open. Click Browse to select the PDF file you want to insert watermarks into.
Inserting Text Watermarks
To insert a text watermark, select the Text check box and type some text in the box. You’ll see a preview in the built-in PDF viewer.

Click Font to select font, size and color for your text watermark.

Click Save As to save the PDF document with a watermark.
Inserting Image Watermarks
To insert an image watermark, select the Image from file checkbox. Next click the … button which is next to it to select an image file. You’ll see a preview in the built-in PDF viewer.

Click Save As to save the PDF document with a watermark.
Setting level of transparency
To make your watermark more opaque or more transparent, just drag the Opacity slider. You’ll see a preview in the built-in PDF viewer.
Setting Watermark’s Position
To move a watermark horizontally, change the number in the Pos X box. You can type the new position or use the small triangle buttons to adjust it.

To move a watermark vertically, change the number in the Pos Y box. You can type the new position or use the small triangle buttons to adjust it.

By default, these positions are measured from the left and from the bottom of the page, but you can change this using the From drop down list. The horizontal position Pos X can be measured from Left, Center and Right. The vertical position Pos Y can be measured from Bottom, Center and Top.

Selecting the Relative check box will switch to a mode that treats Pos X and Pos Y values as percentages of the page size. For instance, Pos X = 50 means half the page width.
Rotating a Watermark
To rotate a watermark, set the rotation angle in degrees in the Rotation box.

0° means the watermark is not rotated at all.

90° means the watermark is rotated to the left.

180° means the watermark is rotated bottom up.

270° means the watermark is rotated to the right.

You can enter any other number between 0° and 360°.
Scaling a Watermark
To scale a watermark, change the number in the Scale box. To make the watermark bigger, just increase the number. To make the watermark smaller, just decrease the number.
Specifying the pages on which a watermark appears
Select Appear on all pages check box to have the watermark on every page of the PDF document.

If you want to have a watermark on selected pages only, select Appear in Pages check box and enter a page range in the box. For example entering 1, 3, 10-13 will insert watermarks on pages 1, 3, 10, 11, 12 and 13.

If you need the watermark on odd pages only, set the Subset drop down list to Odd pages.

If you need the watermark on even pages only, set the Subset drop down list to Even pages.
Displaying Watermarks
Printing watermarks.

You may need to have a watermark that appears if a document is printed, but not visible in case the document is viewed on a computer. Or, you may need to achieve the opposite: have the watermark visible on the computer screen but not in printed format.

Use Show when printing or Show when displaying check boxes in the Appearance group.

To set watermarks to appear behind the text or on top of the text, use the Appear drop down list and set it to on top or behind.
Applying the same watermark to multiple documents
Select a PDF and set up a watermark. Then click Apply to Multiple. The Select Documents window will open. Click Add to add as many PDF files as you need to the list. The watermark will be applied to all of these documents. Click OK to close the Select Documents window.

Click Save As to apply the watermark.
Dealing with PDF files that already have watermarks
When you select a PDF file that already has a watermark, a box will pop asking:

“This document already has a watermark. Do you want to replace it?”

If you answer Yes, all the old watermarks will be removed and you’ll be able to insert a new watermark if you want to.

If you answer No, the old watermarks will be preserved and you’ll be able to add a new watermark on top of them.
Removing watermarks from a PDF document
When you select a PDF file that already contains some watermarks, a box will pop up asking:

This document already has a watermark. Do you want to replace it?”

If you answer Yes, all the old watermarks will be removed and you’ll be able to insert a new watermark if you want to. If you don’t want any new watermarks inserted, just click Save As to save the document without any watermarks.