Cryptogram Quiz: 10 Secret Codes and Ciphers to Crack

This cryptogram quiz asks you to crack secret codes, from the Caesar cipher used by Julius Caesar and the ancient Atbash cipher to ROT13, simple number codes, reversed words and Morse code, plus questions about the famous Enigma machine and the codebreakers of Bletchley Park led by figures such as Alan Turing. Ten questions, each one a small code to solve.

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🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 90 Seconds

Question 1 / 10 Time: 90s

Caesar cipher
In a Caesar cipher where each letter is shifted 3 places forward, KHOOR is the code for which word?
Shift by one
Shift each letter of HAL one place forward in the alphabet. What do you get?
Number code
If A is 1, B is 2 and so on, what word does 3-1-20 spell?
Reversed
Reading backward, what word is hidden in ELZZUP?
Atbash
In the Atbash cipher, A swaps with Z, B with Y and so on. What does SVOOL decode to?
Morse code
In Morse code, what message is sent by three dots, three dashes and three dots?
ROT13
ROT13 shifts every letter 13 places. What does PNG decode to?
Caesar shifts
How many different useful shifts does a Caesar cipher on the 26-letter English alphabet have?
Enigma
Codebreakers at which British site helped break the German Enigma codes during World War II?
Frequency
Which letter is most common in English text, a key clue for breaking substitution ciphers?

Explanations: answer key for all 10 questions

Q1: In a Caesar cipher where each letter is shifted 3 places forward, KHOOR is the code for which word?
Answer: HELLO
Shift each letter back 3 places: K becomes H, H becomes E, O becomes L and R becomes O. The hidden word is HELLO.
Q2: Shift each letter of HAL one place forward in the alphabet. What do you get?
Answer: IBM
H becomes I, A becomes B and L becomes M. Many fans have noticed that the computer HAL in 2001: A Space Odyssey is one letter away from IBM.
Q3: If A is 1, B is 2 and so on, what word does 3-1-20 spell?
Answer: CAT
The 3rd letter is C, the 1st is A and the 20th is T. This simple code is often called the A1Z26 cipher.
Q4: Reading backward, what word is hidden in ELZZUP?
Answer: PUZZLE
Reverse the letters E, L, Z, Z, U, P to get P, U, Z, Z, L, E. Writing words backward is one of the oldest simple codes.
Q5: In the Atbash cipher, A swaps with Z, B with Y and so on. What does SVOOL decode to?
Answer: HELLO
S swaps with H, V with E, O with L and L with O. Atbash was first used with the Hebrew alphabet more than 2,000 years ago.
Q6: In Morse code, what message is sent by three dots, three dashes and three dots?
Answer: SOS
Three dots are S and three dashes are O. SOS became the international distress signal in 1906 because it is so easy to send and recognize.
Q7: ROT13 shifts every letter 13 places. What does PNG decode to?
Answer: CAT
P shifted 13 places is C, N is A and G is T. Because the alphabet has 26 letters, applying ROT13 twice gives back the original text.
Q8: How many different useful shifts does a Caesar cipher on the 26-letter English alphabet have?
Answer: 25
A shift of 0 or 26 leaves the text unchanged, so only 25 shifts actually hide it. That is why Caesar ciphers can be broken by simply trying them all.
Q9: Codebreakers at which British site helped break the German Enigma codes during World War II?
Answer: Bletchley Park
Thousands of people worked at Bletchley Park, including mathematician Alan Turing. Their work is believed to have shortened the war.
Q10: Which letter is most common in English text, a key clue for breaking substitution ciphers?
Answer: E
E appears about 12 percent of the time in English. Codebreakers count letters in a cipher, and the most frequent one often stands for E.

Cryptogram Quiz – The Art of Secret Codes

A cryptogram is a short piece of text written in code. Solving one means finding the rule that turns the coded letters back into plain words. Cryptograms are popular puzzles in newspapers and puzzle books, but they grew out of real secret messages used by rulers, armies and spies for thousands of years.

One of the oldest known methods is the Caesar cipher, named after Julius Caesar, who shifted letters three places in the alphabet to protect his messages. Even older is the Atbash cipher, which swaps the first letter of the alphabet with the last, the second with the second-to-last and so on. It was first used with the Hebrew alphabet.

Simple ciphers like these are easy to break. A Caesar cipher has only 25 useful shifts, so a codebreaker can try them all. For more complex substitution codes, solvers use frequency analysis: counting how often each letter appears. In English, E is the most common letter, followed by letters such as T and A.

During World War II, Germany used the Enigma machine, which changed its settings constantly to create very hard codes. At Bletchley Park in England, codebreakers including Alan Turing built machines that helped read Enigma messages, a story told in many books and films.

Other codes are not secret at all. Morse code turns letters into dots and dashes for telegraphs and radios, and ROT13 is used online to hide spoilers and puzzle answers.

Solving cryptograms builds patience, pattern recognition and logical thinking.

What This Quiz Teaches

This quiz is perfect for puzzle fans, history lovers and young spies.

How the Caesar cipher works
The Atbash and ROT13 ciphers
Number codes and reversed words
Morse code and the SOS signal
Frequency analysis
The Enigma machine and Bletchley Park

Quick Facts About Codes and Ciphers

The pigpen cipher replaces letters with symbols drawn from grids.
Samuel Morse helped develop Morse code in the 1830s and 1840s.
The Arab scholar al-Kindi described frequency analysis in the 9th century.
Bletchley Park is now a museum.
Modern online banking relies on mathematical encryption.
A cipher changes letters, while a code usually replaces whole words.