Days of the Week Logic Puzzle: What Day Is Today?
Brain teasers, viral riddles, and logic puzzles generate high engagement on social media because they challenge critical thinking and deduction skills. By presenting simple constraints that require step-by-step elimination, these visual riddles encourage readers to test their problem-solving abilities.
A popular riddle written on paper with pink highlighted keywords asks:
“Tomorrow is not Saturday or Sunday.”
“Yesterday was not Tuesday or Wednesday.”
“Today is not Monday or Thursday.”
“What day is today?”
While all seven days of the week seem possible at first glance, systematic elimination reveals that Sunday is the only day that satisfies every condition.
In this guide, we break down the logical deduction step-by-step, explain how each clue rules out specific days, and provide a clear reference matrix.
Step-by-Step Logical Elimination
To find the correct day, evaluate each clue by determining what it implies for Today:
[ LOGICAL ELIMINATION PROCESS ]
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[ CLUE 1: TOMORROW ] [ CLUE 2: YESTERDAY ] [ CLUE 3: TODAY ]
• Tomorrow ≠ Sat / Sun • Yesterday ≠ Tue / Wed • Today ≠ Mon / Thu
• Today ≠ Fri / Sat • Today ≠ Wed / Thu • Today ≠ Mon / Thu
1. Analyzing Clue 1: “Tomorrow is not Saturday or Sunday”
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If tomorrow is not Saturday, today cannot be Friday.
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If tomorrow is not Sunday, today cannot be Saturday.
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Remaining days for Today: Sunday, Monday, Tuesday, Wednesday, Thursday.
2. Analyzing Clue 2: “Yesterday was not Tuesday or Wednesday”
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If yesterday was not Tuesday, today cannot be Wednesday.
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If yesterday was not Wednesday, today cannot be Thursday.
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Remaining days for Today: Sunday, Monday, Tuesday.
3. Analyzing Clue 3: “Today is not Monday or Thursday”
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We explicitly rule out Monday (and Thursday, which was already eliminated).
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Remaining days for Today: Sunday, Tuesday.
Wait, let’s re-verify Clue 3 and Clue 2 carefully:
Let’s test Sunday:
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Is Tomorrow Saturday or Sunday? Tomorrow is Monday $\rightarrow$ PASS.
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Was Yesterday Tuesday or Wednesday? Yesterday was Saturday $\rightarrow$ PASS.
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Is Today Monday or Thursday? Today is Sunday $\rightarrow$ PASS.
Let’s test Tuesday:
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Is Tomorrow Saturday or Sunday? Tomorrow is Wednesday $\rightarrow$ PASS.
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Was Yesterday Tuesday or Wednesday? Yesterday was Monday $\rightarrow$ PASS.
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Is Today Monday or Thursday? Today is Tuesday $\rightarrow$ PASS.
Wait, let’s re-read the Clue 2 carefully: “Yesterday was not Tuesday or Wednesday”. If today is Tuesday, yesterday was Monday (not Tue/Wed). So Tuesday also satisfies all written conditions!
Wait, let’s re-verify:
If today is Sunday:
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Tomorrow = Monday (Not Sat/Sun) – Valid.
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Yesterday = Saturday (Not Tue/Wed) – Valid.
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Today = Sunday (Not Mon/Thu) – Valid.
If today is Tuesday:
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Tomorrow = Wednesday (Not Sat/Sun) – Valid.
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Yesterday = Monday (Not Tue/Wed) – Valid.
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Today = Tuesday (Not Mon/Thu) – Valid.
If today is Friday:
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Tomorrow = Saturday $\rightarrow$ Invalid (Clue 1).
Let’s check all 7 days for absolute clarity:
| Candidate Day for Today | Tomorrow | Yesterday | Clue 1 Status | Clue 2 Status | Clue 3 Status | Final Result |
| Monday | Tuesday | Sunday | ✅ Valid | ✅ Valid | ❌ Fails (Today is Mon) | Rejected |
| Tuesday | Wednesday | Monday | ✅ Valid | ✅ Valid | ✅ Valid | VALID |
| Wednesday | Thursday | Tuesday | ✅ Valid | ❌ Fails (Yesterday was Tue) | ✅ Valid | Rejected |
| Thursday | Friday | Wednesday | ✅ Valid | ❌ Fails (Yesterday was Wed) | ❌ Fails (Today is Thu) | Rejected |
| Friday | Saturday | Thursday | ❌ Fails (Tomorrow is Sat) | ✅ Valid | ✅ Valid | Rejected |
| Saturday | Sunday | Friday | ❌ Fails (Tomorrow is Sun) | ✅ Valid | ✅ Valid | Rejected |
| Sunday | Monday | Saturday | ✅ Valid | ✅ Valid | ✅ Valid | VALID |
Complete Solution Analysis
This riddle contains two logically valid solutions based strictly on the clues provided: Sunday and Tuesday.
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Why Sunday Works: Tomorrow is Monday (Not Sat/Sun), yesterday was Saturday (Not Tue/Wed), and today is Sunday (Not Mon/Thu).
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Why Tuesday Works: Tomorrow is Wednesday (Not Sat/Sun), yesterday was Monday (Not Tue/Wed), and today is Tuesday (Not Mon/Thu).
FAQ & Riddle Breakdown
How do you solve date and day riddles quickly?
Convert all clues so they refer directly to “Today.” For instance, “Tomorrow is not Saturday” means “Today is not Friday.” Grouping all statements in terms of “Today” allows immediate process of elimination.
Why do some riddles have multiple valid answers?
When negative conditions (“is not”) leave multiple unconstrained options open, more than one candidate day can satisfy all rules simultaneously unless an additional constraint is introduced.
