Sets or retrieves the current value of the element.

This property applies to elements with an aria role of progressbar, slider, or spinbutton.

The aria-valuemin and aria-valuemax properties together specify the allowable range of values, whereas the aria-valuenow property specifies the value currently selected.

If the current value is not known (for example, an indeterminate progress bar), the author should not  set the aria-valuenow attribute. If the aria-valuenow attribute is absent, no information is implied about the current value. If the aria-valuenow has a known maximum and minimum, the author should provide properties for aria-valuemax and aria-valuemin.

The value of aria-valuenow is a decimal number. If the range is a set of numeric values, then aria-valuenow is one of those values. For example, if the range is [0, 1], a validaria-valuenow is 0.5. A value outside the range, such as -2.5 or 1.1, is invalid.

For progressbar elements and scrollbar elements, assistive technologies should render the value to users as a percent, calculated as a position on the range from aria-valuemin to aria-valuemax if both are defined, otherwise the actual value with a percent indicator. For elements with role slider and spinbutton, assistive technologies should render the actual value to users.

When the rendered value cannot be accurately represented as a number, authors should use the aria-valuetext attribute in conjunction with aria-valuenow to provide a user-friendly representation of the range's current value. For example, a slider may have rendered values of small, medium, and large. In this case, the values of aria-valuenow could range from 1 through 3, which indicate the position of each value in the value space, but the aria-valuetext would be one of the strings: small, medium, or large.

Note: If aria-valuetext is specified, assistive technologies render that instead of the value of aria-valuenow.

Note  For cross-browser compatibility, always use the aria attribute syntax to access and modify aria properties, for example object.setAttribute("aria-valuenow", newValue).

Syntax

HTML
<element aria-valuenow="p" ... >
JavaScript
object.setAttribute("aria-valuenow",value);var value = object.getAttribute("aria-valuenow");