Find out what day of the week any date fell or falls on — past, present, or future — plus when it next repeats on the same weekday.
Pick a date, then click Find Day of the Week
This free day of the week calculator answers a question that's genuinely hard to work out in your head: what weekday did (or will) a specific date fall on? Enter any date — the day you were born, a historical event, or a future deadline — and instantly see whether it's a Monday, Friday, or any other day of the week.
Enter a Date and click Find Day of the Week. The result shows the exact weekday, the date's day-of-year number (1–365 or 366), its ISO week number, whether that year is a leap year, how many days it falls from today, and the next few years the same calendar date will land on the same weekday again.
Anyone curious what day of the week they were born, genealogists and historians verifying event dates, event planners checking whether a date falls on a weekend, and puzzle or trivia enthusiasts exploring calendar patterns like the doomsday algorithm.
The calendar logic behind the result, and a peek at the doomsday algorithm
The result follows the standard Gregorian leap-year rule — divisible by 4, except century years not divisible by 400 — which determines February's length and shifts every later weekday in a leap year.
A calendar date repeats on the same weekday roughly every 5–6 years in a simple pattern, and exactly every 28 years in a cycle free of century-year exceptions, because of how leap years redistribute the extra day.
A classic formula (published by Christian Zeller in the 1880s) computes the day of the week directly from the year, month, and day using modular arithmetic — the same underlying logic modern date libraries use internally.
From picking a date to reading the result
Choose any past, present, or future date using your device's native date picker.
See the exact weekday, day-of-year number, ISO week number, leap-year status, and the next years the date repeats on the same weekday.
A famous historical date and a leap-year date
How to read each element of the result panel
| Result Element | What It Means |
|---|---|
| This date falls on a… (weekday) | The headline answer — the exact weekday (Sunday through Saturday) your selected date falls on, computed from Gregorian calendar rules. |
| Date (e.g. "Feb 29, 2024") | The date you entered, formatted for confirmation so you can verify you picked the right day before relying on the result. |
| Day of Year | The date's ordinal position within its year — from 1 (January 1) to 365 in a common year, or 366 in a leap year. |
| Week Number | The ISO 8601 week number of the date, which can run from week 1 to week 53 and occasionally begins a year in the prior December. |
| Leap Year? | Whether the year of your selected date is a leap year, shown as "Yes" or "No" using standard Gregorian leap-year rules. |
| Days From Today | How far the date is from today — "Today" if it's the current date, "+N days" for future dates, or "−N days" for past dates. |
| Next years on the same weekday | The next few years in which the same month and day land on the same weekday as your selected date — useful for planning recurring events. |
When to reach for this calculator versus NeftCal's other date utilities
| Tool | What It Answers | Dates You Enter | Best For |
|---|---|---|---|
| Day of the Week Calculator (this page) | "What weekday was or will this date be?" | One date | Finding the weekday of any specific date |
| Day Counter | "How many days since or until?" | One date | Counting days measured against today |
| Date Calculator | "What date is N days from this one?" | A date plus a duration | Adding or subtracting days, weeks, or months |
| Date Difference Calculator | "How many days between two dates?" | Two dates | Measuring spans between any two dates |
| Business Days Calculator | "How many working days between dates?" | Two dates | Counting weekdays while skipping weekends and holidays |
| Countdown Calculator | "How much time is left, ticking live?" | One future date + time | Live, second-by-second countdown to an event |
| Age Calculator | "How old am I in years, months, and days?" | A birth date | Exact age from a birth date |
Rule of thumb: use the Day of the Week Calculator when your question is "what weekday is this date." For spans of time, working days, live countdowns, or ages, the matching tool above will give you that answer directly.
What this Day of the Week Calculator does well, and where it has boundaries
Summary: This Day of the Week Calculator instantly finds the weekday for any date, past or future, along with day-of-year, week number, and same-weekday repeat years — free, instant, and entirely client-side. Pair it with the Age Calculator or Date Calculator for related date math.
Common questions about finding a date's day of the week
Explore other time & date tools