JavaScript Date Projects: Calendars, Differences & Clocks

JavaScript Date projects turn the Date object into practical interfaces: date pickers, day-of-week tools, date-difference calculators, clocks, alarms, and start/end date selectors. Start with the project that matches your task, then follow the linked tutorial to see how the individual Date methods work.

The projects below use native JavaScript and progressively combine Date methods, DOM updates, forms, arrays, and event handling.

Calendar and date-picker projects
Date calculations
Clock and timer projects
Related Date tutorials

Calendar and Date-Picker Projects Top ↑

Current month calendar
Build the calendar grid from the first weekday and the last date of the month. Copy a selected calendar date to an input
Turn calendar days into selectable controls and return the chosen value. Calendar with previous/next month and year navigation
Add browsing controls around the base calendar. Linked start and end date calendars
Restrict the second calendar based on the first selected date. Date, month and year dropdowns
Generate select options and preselect the current date.

Date Calculation Projects Top ↑

Difference in days between two dates
Convert calendar dates to comparable UTC day values and calculate a signed or absolute difference. Maturity date after a number of years
Add calendar years correctly instead of approximating every year as 365 days. Find the weekday for an entered date
Validate a calendar date and map getDay() to a weekday name. Find the second Saturday of a month
Use weekday values in a calendar rule.

Clock, Alarm and Stopwatch Projects Top ↑

Clock displays the current date and time with regular updates. Alarm Clock compares the current time with a user-selected alarm. Stopwatch measures elapsed duration between start, pause/reset operations.

Before modifying these projects, review creating Date objects, timestamps with getTime(), getDay(), getMonth(), and the JavaScript Date reference.

Date Reference

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

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