This element provides a list of answers with blank boxes, which can contain any marks - from marker filling to light pencil checks.

You can directly specify the recognition accuracy for this element so that even the lightest marks are detected.


The element declaration begins with ?checkbox=[name] statement and ends with &checkbox statement. These statements must be placed on separate lines.

name property is used as an element’s identifier in recognition results and is displayed as a label on the form; for example, “Food preference”.

Answers are provided using standard content elements that are placed inside the checkbox declaration.


The checkbox element can be customized by adding optional attributes to it.

An attribute is written as [attribute_name]=[value]. Each attribute must be placed on a new line immediately after the opening ?checkbox= statement or another attribute, and must begin with a tab character.

Attribute Default value Description Usage example
threshold 3 Set the recognition accuracy for the answer boxes, from 0 to 100. Lower values allow even the lightest marks to be recognized, but may cause dirt or paper defects to be treated as marks. Higher values require a more solid fill and may cause pencil marks or small checks to be ignored.

Checkbox threshold
hide_name false Set to true to hide the label (name) of the checkbox element. hide_name=true
bubble_size Normal Size of boxes: extrasmall, small, normal, large, or extralarge. bubble_size=large
bubble_type square Bubble style: round or square. bubble_type=round
align left Horizontal alignment of checkbox element: left, center or right. align=center
font_style regular The font style for a checkbox label: bold, italic or underline.
Several font styles can be combined by listing them separated by commas.
font_style=bold, italic
font_size 12 Font size for the checkbox label. font_size=16

Allowed child elements


?checkbox=Food preference:

Checkbox example