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The clientTop property holds a value giving the location of the top of the client area relative to the location described by the offsetTop property.  It is a read-only, integer property of element.  The value is expressed in pixels.  

As it happens, all that lies between the two locations (offsetTop and client area top) is the element's border.  This is because the offsetTop indicates the location of the top of the border (not the margin) while the client area starts immediately below the border, (client area includes padding.)  Therefore, the clientTop value will always equal the integer portion of the .getComputedStyle() value for "border-top-width". (Actually might be Math.round(parseFloat()).)  For example, if the computed "border-top-width" is zero, then clientTop is also zero.

Gecko-based applications support clientTop starting with Gecko 1.9 (Firefox 3, implemented in bug 111207). This property is not supported in Firefox 2 and earlier.

Syntax

var top = element.clientTop;

Example

In the following illustration, the client area is show in white.  (The segments labeled "Top", "Right", etc. have no significance regarding the client area.)  The clientTop value is the distance from where the margin (yellow) area ends and the padding and content areas (white) begin. 

padding-top

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

padding-bottom

Left Top Right Bottom margin-top margin-bottom border-top border-bottom

Notes

clientTop was first introduced in the MS IE DHTML object model.

Specifications

Specification Status Comment
CSS Object Model (CSSOM) View Module
The definition of 'clientTop' in that specification.
Working Draft  

See also