SpinBox

A spin box, also known as a spin control or up-down control, is a user interface element that allows entering a numeric value by either typing it directly or incrementing and decrementing with small arrows. The typical layout includes a text display of the current value and one or two controls to adjust it.

Core features commonly exposed by spin boxes include minimum and maximum bounds, a current value, and a step size that determines how much the value changes with each increment or decrement. Some implementations support a larger step when the user holds a modifier key or uses page-up/page-down interactions. Spin boxes may handle integers only or support floating-point numbers, depending on the variant. They can be editable or read-only, and some offer optional wrap-around at the bounds.

Common interactions include clicking the up or down arrows to change the value, typing a number directly into the field, and using keyboard shortcuts such as the up/down arrows or page up/page down keys. Mouse wheel support and input validation are typical features to ensure values stay within defined limits. Localization considerations include proper handling of decimal separators and number formats.

Variants and implementations differ across frameworks. Notable examples include Qt's QSpinBox and QDoubleSpinBox; GTK's SpinButton; Windows' NumericUpDown; and HTML5 input type="number" with spinner controls that are browser-dependent. Accessibility considerations often address descriptive labels, keyboard operability, and visible value updates for screen readers.

Spin boxes are commonly used in forms and settings where precise numeric input is required, offering a compact alternative to sliders when exact values are important or when input accuracy is preferred. They complement other controls by combining direct entry with convenient stepwise adjustment.