Coding Decoding Tricks for CLAT | Letter Shift Codes

📑 On this page

⚡ The 20-second answer

You get a word and its code, and must run the same rule on a new word. Write alphabet positions under both and take the difference row: it reveals a constant shift, a shift pattern, a mirror (pairs add to 27) or a reshuffle. The number one trap: reading the gap the wrong way round.

🎬 The 30-second story

The hostel group-chat cipher

“New rule: in the group chat, MESS is NFTT. The warden will never crack it.”

📱

Meher

Meher invents a code for her hostel wing.

“Easy. Midnight MAGGI is LZFFH. Order placed.”

🍜

Aarav

Aarav cracks it in two seconds. Or thinks he does.

“M is 13, N is 14. Meher moved letters forward; you moved them back.”

🖊️

Zoya

Zoya writes positions under each letter.

“And the warden decoded it with an alphabet chart.”

😱

Meher

A constant shift falls to anyone who subtracts.

Tara's verdict: Every letter code is a rule you read off positions. M(13) → N(14) is +1 for every letter, so MAGGI is NBHHJ. Check the direction of the gap, and check it on every letter, not just the first.

How does CLAT word coding–decoding questions?

Coding sat in the 2018–2020 papers as one-line puzzles. Six real stems, and what each really asks:

Real stem (paper)	Code family	What it really asks
If VOLKSWAGEN is written as UQKMRYZIDP, SWITZERLAND is written as? (2018 Q95)	Shift pattern	Repeat the shift row over a longer word
If TEACHER is coded CAHEETR and STUDENT is DUETNST, code SUCCESS (2018 Q123)	Rearrangement	Track positions, not letters
If DECEMBER is AUGUST, MARCH is MAY… JUNE is? (2018 Q110)	Hidden property	Letter count = month number
If 'e' and every alternate letter from 'e' is a capital, code the sixth month from March (2019 Q1)	Rule in words	Apply a stated rule, letter by letter
If Clever is XOVEVI, Smart is? (2019 Q2)	Mirror	Pairs of positions add to 27
If 367 means 'I am happy'… which digit means 'and'? (2020 Q130)	Sentence code	Shared word = shared digit

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What is a letter code, really?

A letter code is arithmetic in disguise. Swap each letter for its position (A = 1 … Z = 26) and the word becomes a row of numbers; the code is a second row. Subtract and the rule shows itself. Two anchors help: EJOTY sits at 5, 10, 15, 20, 25, and a letter's mirror is 27 minus its position.

🔤 Letter line

Meher's hostel code on the alphabet strip

Top: letter · middle: position (A = 1) · bottom: reverse position (Z = 1). Gold = EJOTY anchors (5, 10, 15, 20, 25).

M +1 N

E +1 F

S +1 T

Rule: Flat difference row: a constant +1 shift.

🧩 At a glance

The six code families CLAT draws from

➡️Constant shift

Every letter moves the same places. CAT → ECV is +2 each.

🔁Shift pattern

The shift changes with position: −1, +2, −1, +2 or +1, +2, +3.

🪞Mirror

Positions add to 27. BAT → YZG.

🔀Rearrangement

Same letters, new order: a map of positions.

🔢Number and sentence codes

Words become symbols. Compare lines and cross off.

🗣️Substitution

'Sky is called sea.' Answer first, translate once.

📌 The 27 rule

If a letter and its code letter add to 27 every time, it is a mirror code. Know A–Z, E–V, H–S, M–N cold. A constant sum other than 27 (say 28) is a mirror plus a shift.

How do you crack any code in 30 seconds?

1
Stack
Word above code, positions beneath. Lengths differ? Look for a hidden property such as letter count.
2
Subtract
Code minus word, letter by letter. Past Z it wraps: Z(26) → C(3) is −23, really +3.
3
Name
Flat row = constant shift; repeating row = pattern; sums of 27 = mirror; same letters = rearrangement.
4
Apply
Run the rule on the new word one letter at a time, in pencil.
5
Check
Kill options with the first, last and one middle letter. First letters are often shared on purpose.

Which code patterns and traps does CLAT use?

Shift patterns that change by position

The next rung up: a row that changes along the word.

🔤 Letter line

A growing shift: REELS

R +1 S

E +2 G

E +3 H

L +4 P

S +5 X

Rule: The two Es code differently (G, then H): the shift belongs to the position, not the letter.

Mirror codes, and a mirror with a twist

🔤 Letter line

A mirror code: MOCK

M ↓ N

O ↓ L

C ↓ X

K ↓ P

Rule: As shifts: +1, −3, −5, +5, nonsense. As sums: 27 every time. Mirror.

Random-looking row? Add instead of subtracting. Sum 27 is a pure mirror; 28 is mirror then +1; 26 is mirror then −1.

Rearrangement codes

When the code reuses the word's letters, stop subtracting. Number the positions 1 to n, write which one lands in each slot, and apply that position map to the new word.

⚠️ Repeated letters lie

Never ask 'where did the S go?' when the word has three. Ask 'which position went first?' In 2018 Q123, SUCCESS has three Ss and two Cs; only the position map gives one answer.

Number, sentence and substitution codes

Sentence codes: take two lines at a time; the word they share matches the symbol they share, and order means nothing. Substitution: if juice is called milk and milk is called tea, a cow gives milk, so answer tea. Translate once.

⚔️ Side by side

Letter codes vs sentence codes

🔤Letter codes

the rule lives in the alphabet

•Positions under both rows
•Difference row or sum row
•Apply letter by letter

💬Sentence codes

the rule lives in the overlaps

•Compare two lines at a time
•Shared word = shared symbol
•Finish the rest by elimination

Test	Letter codes	Sentence codes
Main tool	Difference row	Overlap table
Classic trap	Shift read backwards	Matching by position in the line
Past paper	2018 Q95	2020 Q130

Can you solve coding–decoding step by step? Four worked examples

✍️ Worked example Warm-up ⏱ 25 sec

The fest code with a wrap

In the fest committee's code, ZEBRA is written as CHEUD. How is QUIZ written?

1
Stack: 26 5 2 18 1 over 3 8 5 21 4.
2
Subtract: 3 − 26 = −23, which wraps to +3; the rest are +3.
3
Name: constant shift of +3.
4
Apply: Q → T, U → X, I → L, Z wraps to C.

Answer: QUIZ → TXLC

⚡ The exam-hall shortcut

Skip the Z: E → H and B → E are both +3. Wraps only matter at the ends.

✍️ Worked example CLAT level ⏱ 45 sec

The sum that isn't 27

In a code, GOLD is written as UMPX. How is KICK written?

1
Stack: 7 15 12 4 over 21 13 16 24.
2
Subtract: −12, −2, +4, −6. No pattern.
3
Add instead: 28 every time. Name: mirror, then +1.
4
Apply: K(11) → 17 = Q; I(9) → 19 = S; C(3) → 25 = Y; K → Q.

Answer: KICK → QSYQ

⚡ The exam-hall shortcut

Code position = 28 − letter position.

✍️ Worked example CLAT level ⏱ 40 sec

The cricket reshuffle

In a code, CRICKET is written as IRCCTEK. How is BATTING written?

1
Stack: same letters as CRICKET, so a rearrangement.
2
Map: the code reads positions 3, 2, 1, 4, 7, 6, 5.
3
Name: flip the first three, keep the middle, flip the last three.
4
Apply: B1 A2 T3 T4 I5 N6 G7 → T A B T G N I.

Answer: BATTING → TABTGNI

⚡ The exam-hall shortcut

Say the rule in words. With two Ts, tracking letters leaves you guessing which T went where.

✍️ Worked example Tricky ⏱ 60 sec

The midnight-maggi chat

Meher's wing now codes whole words as numbers, so the warden sees only digits. '5 8 2' means 'maggi tonight terrace'. '2 9 4' means 'terrace party cancelled'. '8 4 7' means 'cancelled tonight sorry'. Digits are not in word order. Someone posts '5 9 8'. What does it say?

1
Stack the messages as sets, not ordered lines.
2
Overlap: lines 1 and 2 share 2 and 'terrace'; lines 1 and 3 share 8 and 'tonight'; lines 2 and 3 share 4 and 'cancelled'.
3
Eliminate: 5 = maggi, 9 = party, 7 = sorry.
4
Check: each line reads back correctly.

Answer: '5 9 8' = maggi party tonight

⚡ The exam-hall shortcut

Three overlaps give three words free; elimination gives the rest.

How did CLAT ask coding–decoding?

One real question from each main family. The 2018 paper's options 1–4 are shown as A–D.

📝 Asked in CLAT 2018 · Q95 Shift pattern

If “VOLKSWAGEN” is written as “UQKMRYZIDP” then “SWITZERLAND” is written as ___?

ARVHSYDFPMOD

BTXJUAFSMBOE

CRYHYVGQNZPE

DRYHVYGQNZPC

Reveal answer + reasoning

Answer: D

Subtract: V → U is −1, O → Q is +2, and the row repeats −1, +2 across all ten letters. Apply it to SWITZERLAND (diagram below): RYHVYGQNZPC. Answer D. Three options start with R, so check the last letter first: only D ends in C.

Why the others fail

A — −1 on six letters, then no pattern.
B — A flat +1, which does not even produce VOLKSWAGEN's code.
C — Swaps the 4th and 5th letters and ends in E, which needs +1 on D.

🔤 Letter line

2018 Q95: the −1, +2 rhythm carried into SWITZERLAND

S -1 R

W +2 Y

I -1 H

T +2 V

Z -1 Y

E +2 G

R -1 Q

L +2 N

A -1 Z

N +2 P

D -1 C

Rule: The 11th letter continues the rhythm: D − 1 = C.

📝 Asked in CLAT 2018 · Q123 Rearrangement

If TEACHER is coded as CAHEETR and STUDENT is coded as DUETNST, then what is the code for SUCCESS?

ACECSUSS

BCCEUSSS

CSCUSCES

DUCSECSS

Reveal answer + reasoning

Answer: B

Same letters, so map positions. STUDENT → DUETNST reads positions 4, 3, 5, 2, 6, 1, 7; TEACHER → CAHEETR confirms it. For SUCCESS (S1 U2 C3 C4 E5 S6 S7): C, C, E, U, S, S, S. CCEUSSS, answer B.

Why the others fail

A — E second, but position 3 is C.
C — Starts with S, but position 4 is C.
D — Starts with U, position 2, not 4.

📝 Asked in CLAT 2019 · Q2 Mirror code

If in a certain code, 'Clever' is written as 'XOVEVI', then 'Smart' would be written as

AHZNGI

BHNZIG

CGHNGI

DGIHZN

Reveal answer + reasoning

Answer: B

Our solution (CLAT 2019 has no official key). Subtracting gives nonsense. Add: C(3) + X(24), L(12) + O(15), R(18) + I(9) all make 27. Mirror. Apply: S → H, M → N, A → Z, R → I, T → G. HNZIG, answer B.

Why the others fail

A — Right letters, wrong order.
C — Two Gs and no Z, so a wrong letter.
D — An anagram. A mirror keeps the word's order.

🔤 Letter line

2019 Q2: SMART through the mirror

Top: letter · middle: position (A = 1) · bottom: reverse position (Z = 1). Gold = EJOTY anchors (5, 10, 15, 20, 25).

S ↓ H

M ↓ N

A ↓ Z

R ↓ I

T ↓ G

Rule: Each pair adds to 27.

📝 Asked in CLAT 2020 · Q130 Sentence code

If '367' means 'I am happy'; '748' means 'you are sad' and '469' means 'happy and sad' in a given code, then which of the following represents 'and' in the code?

Reveal answer + reasoning

Answer: C

Overlap: 367 and 469 share 6 and 'happy', so 6 = happy. 748 and 469 share 4 and 'sad', so 4 = sad. In 469, 9 = and. Answer C.

🔬 Option autopsy

2020 Q130: why each wrong digit tempts you

Which digit represents 'and'?

A 3 Tag it

❓ Not supported by the text

3 is 'I' or 'am', and it is not in 469.

B 6 Tag it

🎯 Targets the wrong claim

Shared by 367 and 469: 'happy'.

C 9 Tag it

✅ Correct

The only digit left in 469.

D 4 Tag it

🎯 Targets the wrong claim

Shared by 748 and 469: 'sad'.

❓ Not supported by the text🎯 Targets the wrong claim✅ Correct

Guess the trap behind each option, then tap to check. Wrong options fail in a handful of predictable ways.

💥 Myth vs fact

Myth vs fact: coding–decoding

🙅 Myth

Check the first letter and pick the option.

Tap to bust it →

✅ Fact

In 2018 Q95, three of four options start with R. Check the last letter too.

🙅 Myth

If the difference row looks random, the code has no rule.

Tap to bust it →

✅ Fact

It usually hides a mirror (add the positions) or a rearrangement. Test both.

🙅 Myth

In sentence codes, the first word matches the first symbol.

Tap to bust it →

✅ Fact

Order means nothing. In 2020 Q130, 'happy' is the last word of 'I am happy' but its digit 6 is the middle digit of 367.

🙅 Myth

Coding questions are a gamble under time pressure.

Tap to bust it →

✅ Fact

With a difference row a five-letter code takes 20 seconds, and you can be certain before you mark.

Can you crack these five codes?

🎯 Quick quiz

Coding–decoding quiz

0 / 5

Q1. If BRIEF is coded as DTKGH, how is CLAUSE coded?

Q2. In a code, VERDICT is written as EVIWRXG. How is BAIL written?

Kabir's café runs its staff chat in code, because customers waiting at the counter can see the tablet. On Saturday three messages go out. 'pik tor lam' means 'cold coffee ready'. 'lam sev dun' means 'ready for pickup'. 'dun tor vix' means 'pickup cold sandwich'. The code words in each message are not in the same order as the English words. The barista now wants to tell the delivery rider that a sandwich is waiting.

Q3. What is the code for 'sandwich'?

At the college fest treasure hunt, every clue card uses a swapped vocabulary to slow teams down. On the cards, 'library' is called 'canteen', 'canteen' is called 'hostel', 'hostel' is called 'gate', and 'gate' is called 'library'. Meher's team reaches the last card. It says the prize is waiting at the place where students go to borrow books. To claim it, the team must name the place in the code used on the cards.

Q4. Which word must Meher's team say?

Q5. If CASE is coded as DCVI, how is PLEA coded?

🎯 Coding–decoding in a nutshell

A letter code is two rows of numbers: subtract to find shifts, add to find mirrors.
Flat row = constant shift; repeating or growing row = shift pattern; sum of 27 = mirror.
Same letters in a new order = rearrangement: map positions, never letters.
Sentence codes: two lines share one word and one symbol. Order inside a line means nothing.
Substitution: answer the real question, then translate exactly once.
Check options from the last letter: first letters are often shared on purpose.

📎 Cheat sheet

'X is written as Y', same length → letter code → positions under both, difference row
Code has the same letters → rearrangement → number positions 1…n, write the map
Pairs add to 27 (or another constant) → mirror (plus shift) → code = constant − position
'… means …' lines → sentence code → overlap two lines at a time, then eliminate
'X is called Y' → substitution → answer in plain words, translate once
Word and code differ in length → hidden property → count letters, try a month's number
Anchors: EJOTY = 5, 10, 15, 20, 25; mirror pairs A–Z, E–V, H–S, M–N

Frequently asked questions

What is the fastest trick for coding–decoding questions?

Write the alphabet position under every letter of the word and its code, then subtract. A flat row is a constant shift, a repeating row is a shift pattern, and if the positions add to 27 it is a mirror. Writing the row takes about ten seconds and replaces guessing with certainty.

How do I remember alphabet positions quickly?

Learn EJOTY: E is 5, J is 10, O is 15, T is 20 and Y is 25. Every other letter is at most two steps from one of these anchors. For mirrors, remember that a letter and its opposite add to 27, so M (13) pairs with N (14).

Does modern CLAT still ask coding–decoding?

It was a regular feature in 2018 and 2019, and 2020 still had a sentence-code question. Since then LR has been mostly passages, but CLAT 2025 brought back a seating set, so short analytical questions can return. One coding question is cheap marks if you have the method ready.

What do I do when the code has the same letters as the word?

Stop subtracting, because it is a rearrangement. Number the word's positions 1 to n, write which position appears in each slot of the code, and apply that position map to the new word. Use the example word with no repeated letters to build the map.

How do I solve sentence codes like '367 means I am happy'?

Take two sentences at a time. The word they share matches the symbol they share. Write each match down, then fill in the rest by elimination. Never match by position: the order of symbols inside a code line usually differs from the order of the words.