JavaScript Date getDate() Method

What You’ll Learn

getDate() returns the calendar day of the month (1–31) from a Date object in local time. This guide covers syntax, five examples, comparisons with similar methods, and safe patterns for date math.

Introduction

Dates power scheduling, billing, dashboards, and “posted on” labels. The JavaScript Date object stores an instant in time; getter methods like getDate() break that instant into human-friendly parts using the user’s local timezone.

If you need the weekday name or index, use getDay() instead—getDate() answers “what number day of this month?”

Understanding the getDate() Method

Date.prototype.getDate() is a zero-argument instance method. It never mutates the original Date—it only reads the day-of-month component according to local time rules.

Combine it with getMonth(), getFullYear(), and getHours() to assemble custom formats, or use toLocaleDateString() when locale-aware formatting is enough.

📝 Syntax

dateObj.getDate()

Parameters

• None.

Return value

• Integer 1–31 for a valid date in local time.
• NaN if dateObj is an invalid Date.

Examples Gallery

Open DevTools Console (F12) or use Try-it links. Fixed dates use the constructor form new Date(year, monthIndex, day) to avoid string parsing surprises.

const today = new Date();
const dayOfMonth = today.getDate();

console.log("Today is day", dayOfMonth, "of the month.");

Today is day 17 of the month.

const march15 = new Date(2026, 2, 15);

console.log(march15.getDate());        // 15
console.log(march15.getMonth());       // 2 (March)
console.log(march15.getFullYear());    // 2026

15
2
2026

function safeGetDate(date) {
  if (!(date instanceof Date) || Number.isNaN(date.getTime())) {
    return null;
  }
  return date.getDate();
}

console.log(safeGetDate(new Date()));           // e.g. 17
console.log(safeGetDate(new Date("not-a-date"))); // null

17
null

function displayDateInfo(date) {
  const day = date.getDate();
  const month = date.toLocaleString("en-US", { month: "long" });
  const year = date.getFullYear();
  return month + " " + day + ", " + year;
}

console.log(displayDateInfo(new Date(2026, 6, 4)));
// July 4, 2026

July 4, 2026

const daysToAdd = 7;
const future = new Date(2026, 0, 28); // Jan 28, 2026

future.setDate(future.getDate() + daysToAdd);

console.log(future.getDate());     // 4
console.log(future.getMonth());    // 1 (February)
console.log(future.getFullYear()); // 2026

4
1
2026

🚀 Common Use Cases

• Calendar cells — highlight today with getDate().
• Due dates — show “due on the 25th” from a Date.
• Billing cycles — detect month-end with getDate() vs next day.
• Relative deadlines — add N days via setDate.
• Form defaults — pre-fill day dropdowns on date pickers.
• Logging — include day-of-month in custom timestamp strings.

📝 Notes

• getDate() is local; use getUTCDate() when you standardize on UTC.
• Do not confuse with getDay() (weekday index).
• Invalid dates propagate NaN—validate first.
• Month length varies; let setDate handle overflow instead of manual tables.
• For user-facing strings, prefer locale formatters over hard-coded English month names.
• Immutable-style code can copy with new Date(date) before mutating via setDate.

💡 Best Practices