Find what day of the week any date falls on — including what day it will be in a number of weeks or days from now, or what day it was some days ago. Look up historical and future dates, Australian public holidays, and interesting date facts.
To answer "what day will it be in N days" or "what day was it N days ago," pick that date on a calendar (or add/subtract N from today using the Days From Today calculator) and enter it below — the result shows the exact weekday instantly, along with how many days that is from today.
Notable Australian Dates
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A common way to ask this question is "what day will it be in 60 days" or "what day was it 45 days ago," without a specific calendar date in mind. Because the answer depends entirely on today's date, it changes every day — the table below shows a worked example anchored to a Saturday, so you can see the pattern; use the calculator above (or the Days From Today calculator to find the calendar date first) for a result based on today's actual date.
| Question | Days offset | Example result (from a Saturday) |
|---|---|---|
| What day will it be in 2 weeks? | +14 days | Saturday (2 weeks from any day is always the same weekday) |
| What day will it be in 30 days? | +30 days | Monday |
| What day will it be in 45 days? | +45 days | Tuesday |
| What day will it be in 60 days? | +60 days | Wednesday |
| What day will it be in 75 days? | +75 days | Thursday |
| What day will it be in 90 days? | +90 days | Friday |
| What day was it 30 days ago? | −30 days | Thursday |
| What day was it 45 days ago? | −45 days | Wednesday |
| What day was it 60 days ago? | −60 days | Tuesday |
The day of the week for any date can be determined algorithmically without needing a calendar, using methods like Zeller's Congruence, the Doomsday algorithm, or Tomohiko Sakamoto's formula (used internally by this calculator). The Gregorian calendar's day-date pattern repeats every 400 years (146,097 days), which is why perpetual calendar tricks work at all — the pattern of which dates fall on which weekdays eventually cycles back exactly.
Australian Federation occurred on 1 January 1901 (a Tuesday). Decimal currency was introduced on 14 February 1966 (a Monday — replacing pounds, shillings and pence with dollars and cents at a rate of 2:1).
Beginner:
Wednesday — 21 days is an exact multiple of 7, so the weekday repeats.
Monday — same reasoning, exactly one week back.
Advanced:
100 ÷ 7 = 14 remainder 2, so add 2 weekdays to Saturday: Sunday, then Monday. Answer: Monday.
Saturday — famously the "Y2K" date, verified by the calculator above.
| Date | Day | Event |
|---|---|---|
| 1 January 1901 | Tuesday | Australian Federation |
| 25 April 1915 | Sunday | ANZAC Day — Gallipoli landing |
| 5 June 1942 | Friday | Battle of Midway begins |
| 20 July 1969 | Sunday | Apollo 11 Moon landing |
| 1 January 2000 | Saturday | Y2K / Millennium |
What day will it be in a certain number of days?
Add that many days to today's date (or use the Days From Today calculator to find the date first), then enter the result into the calculator above to see the exact weekday. As a shortcut: any exact multiple of 7 days lands on today's weekday; other offsets shift forward by the remainder when divided by 7.
What day was it a certain number of days ago?
Same idea in reverse — subtract the number of days from today to find the calendar date, then enter it above. For a quick estimate without a calculator: divide the number of days by 7, and shift backwards by the remainder from today's weekday.
How do you calculate the day of the week for any date?
The most efficient algorithm is Tomohiko Sakamoto's: convert month (Jan=11, Feb=12 of previous year), use the formula: y = year; if month <= 2: y--; era = y/400 - y/100 + y/4; day = (era + y + day-of-month + (month*2.6 - 0.2) + 1) % 7. Result: 0=Sunday, 1=Monday...6=Saturday. For historical curiosity, the calculator above handles all valid Gregorian dates.
What day of the week was Australia Day 2025?
Australia Day 2025 (26 January) fell on a Sunday. Because the public holiday was on a Sunday, the gazetted public holiday was observed on Monday 27 January 2025 under the Public Holidays Act.
Why does 2 weeks from today always land on the same weekday?
Because 14 days is exactly 2 full 7-day weeks, and the 7-day cycle repeats perfectly. Any offset that's an exact multiple of 7 — 1 week, 2 weeks, 10 weeks — always returns to the same weekday you started from.