Online Fullscreen Clock with Digital & Analog Modes Display a beautiful full-screen digital or analog clock for presentations and ambient displays.

The tool uses the `setInterval` function to update the time every 1000 milliseconds, or 1 second, ensuring a smooth and accurate display of the current time. In digital mode, it utilizes Date methods such as `getHours`, `getMinutes`, and `getSeconds` to extract the relevant time components, which are then formatted with zero-padding using the `padStart` method to maintain a consistent display format. The analog display relies on CSS transforms to position the clock hands, calculating their angles based on the current hour, minute, and second values, with adjustments for smooth sweeping motions.

Under the hood, the tool employs React's `useState` and `useEffect` hooks to manage state changes and side effects, such as updating the display when the user toggles between digital and analog modes or adjusts the time format settings. The `useCallback` hook is used to memoize the `drawAnalog` function, which is responsible for rendering the analog clock face on a HTML canvas element, using 2D drawing context methods like `clearRect`, `arc`, and `stroke`. The Fullscreen API is used to enter and exit full screen mode, with event listeners attached to handle changes in the document's fullscreen state. The tool also uses JavaScript's built-in `Date` object to get the current time and format it according to the user's preferences, with options for 12 or 24-hour formats and display of seconds and date information.

The canvas element used for the analog clock face is dynamically resized based on its parent container's dimensions, ensuring a responsive and adaptable display that can be easily integrated into various presentation settings. The tool's use of React and JavaScript technologies enables a flexible and efficient implementation, with a focus on delivering a high-quality user experience through smooth animations and precise timekeeping. The `toLocaleDateString` method is used to format the date according to the user's locale, providing a localized display of the current date.