পঞ্জিকা বা ক্যালেন্ডার হলো দিনসমূহকে হিসাব করার জন্য ব্যবহৃত পদ্ধতি।

A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a physical record of such a system. A calendar can also mean a list of planned events, such as a court calendar, or a partly or fully chronological list of documents, such as a calendar of wills.