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Academy11+

11+ Verbal reasoning · Topic explained

Letter codes

How does CAT turn into DBU?

The big idea

Every letter makes the same move along the alphabet. Find the move, then copy it.

Picture it

A spy's decoder: each letter slides along the alphabet by the same number of steps.

Key words

code
a secret way of writing a word
move
how many places each letter jumps along the alphabet
decode
turn a code back into the word: make the move backwards
wrap round
after Z, carry on from A again

Worked examples

  1. 1Warm-up

    If CAT is written DBU, how is DOG written?

    • C → D, A → B, T → U: every letter moves on 1.
    • D → E, O → P, G → H
    • DOG is written EPH.
  2. 211+ standard

    If PLANE is coded RNCPG, what does VKOG mean?

    • P → R, L → N, A → C…: every letter moves on 2.
    • To decode, move back 2: V → T, K → I, O → M, G → E.
    • VKOG means TIME.
  3. 311+ standard

    If FISH is coded GKVL, what is the code for BIRD?

    • The moves grow: F +1, I +2, S +3, H +4.
    • B +1 = C, I +2 = K, R +3 = U, D +4 = H
    • BIRD → CKUH
  4. 411+ standard

    If WAX is coded ZDA, what is the code for YES?

    • Every letter moves on 3. X goes Y, Z, then wraps round to A.
    • Y → B (wrapping round), E → H, S → V
    • YES → BHV

The common mistake

The mistake

Count the letter you start on as step one.

Instead

Count the jumps, not the letters: C to F is three jumps.

Why: Counting the starting letter makes every answer one letter short.

Where it comes up in the 11+

Letter codes are a standard GL verbal reasoning question, and the alphabet is printed for you. CEM-style papers use them less often.

The video

Video coming soon

We're making a short video that explains letter codes step by step. Until then, everything it covers is on this page.

Free printable

Letter codes worksheet

Practice questions on this topic to print and try on paper, at home or on the way to school.

Download the worksheet (PDF)

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Quick quiz

Have a go first, then tap to see the answer.

  1. 1. If HAT is written IBU, how is PEN written?

    • QFO
    • OFM
    • QEN
    • RGP
    Show the answer

    QFO

    Every letter moves on 1: P → Q, E → F, N → O.

  2. 2. If GOLD is coded IQNF, what is the code for BELL?

    • DGNN
    • CFMM
    • DGMM
    • EHOO
    Show the answer

    DGNN

    Every letter moves on 2: B → D, E → G, L → N, L → N.

  3. 3. In a mirror code, A swaps with Z and B swaps with Y. What does C become?

    • W
    • X
    • D
    • Y
    Show the answer

    X

    C is third from the start, so it swaps with the third from the end: X.