# Coding Decoding Questions — Free Verified Practice | Deduce > Practise coding decoding questions free: align the letters, measure the shift, and test the rule on a second word before answering. Worked solutions included. Source: https://deducepuzzles.com/reasoning/coding-decoding --- # Coding decoding questions — free, machine-verified practice Coding-decoding is the most mechanical family in the reasoning section and one of the fastest to clear once the alphabet positions are automatic. It is also the topic where a single untested assumption costs an entire set, because the same first letter can be consistent with three different rules and only the second word separates them. ## How to solve coding decoding questions by measuring the shift - Know the alphabet positions cold A is 1, E is 5, J is 10, O is 15, T is 20, Y is 25. Anchoring on those six lets you find any letter's position in under a second by counting from the nearest anchor. Every method below assumes this is instant; if it is not, the topic will always feel slow. - Write the pair vertically and subtract Put the original word above its code, letter under letter, and write the numeric difference beneath each column. The differences make the rule visible at a glance — all the same means a constant shift, alternating signs mean a two-step rule, and a decreasing run usually means positions are being used. - Check reversal before anything exotic If the differences look random, read the code backwards against the word. A large share of these questions are a simple shift applied to the reversed word, and testing that one hypothesis takes five seconds. Do it before hunting for a more complicated pattern. - Validate the rule on a second word, always A rule that explains one word is a guess. Papers deliberately construct sets where two rules fit the first example and diverge on the second, so a candidate who applies immediately gets a plausible wrong answer. If only one example is given, test your rule by re-encoding it and confirming you land back on the code. ## The rules that cover most coding-decoding sets | What the differences look like | The rule | | --- | --- | | Same number in every column | Constant forward or backward shift | | +1, −1, +1, −1 | Alternating shift | | Differences grow 1, 2, 3, 4 | Positional shift by letter index | | Random until read backwards | Word reversed, then shifted | | Letter maps to its 27-minus position | Opposite-letter (A↔Z) coding | | Digits appear in the code | Letter replaced by its alphabet position | ## Practise coding decoding questions right now Every question below was generated by the same engine that mints the Deduce daily puzzle, and machine-proven to have exactly one correct answer before it reached this page. The walkthrough is the engine's own, step for step. ### Question 1 If "ROAD" is written as "JGSV" in a certain code, how is "BIRD" written in that code? Determine the coding pattern from the example and apply it to the target word. - SZIU - TAJV - VCLX - RYHT - UBKW - Compare "ROAD" → "JGSV": each letter shifts forward by 18 (wrapping past Z). - Apply the same +18 shift to "BIRD": B→T, I→A, R→J, D→V. - So "BIRD" is written as "TAJV". ### Question 2 If "FIRE" is written as "NQZM" in a certain code, how is "MILK" written in that code? Determine the coding pattern from the example and apply it to the target word. - TPSR - SORQ - UQTS - VRUT - WSVU - Compare "FIRE" → "NQZM": each letter shifts forward by 8 (wrapping past Z). - Apply the same +8 shift to "MILK": M→U, I→Q, L→T, K→S. - So "MILK" is written as "UQTS". ### Question 3 If "BIRD" is written as "WDMY" in a certain code, how is "MILK" written in that code? Determine the coding pattern from the example and apply it to the target word. - FBED - HDGF - GCFE - JFIH - IEHG - Compare "BIRD" → "WDMY": each letter shifts forward by 21 (wrapping past Z). - Apply the same +21 shift to "MILK": M→H, I→D, L→G, K→F. - So "MILK" is written as "HDGF". ## Common mistakes ### Applying a rule confirmed on one letter The first letter of a word is consistent with many rules. Confirm across the whole word and, where possible, a second word, before you encode the target. Almost every wrong option in this family is the result of a rule that was right about one column. ### Losing the wrap-around Shifting Z forward by two gives B, not a letter past the alphabet. Treat the alphabet as a circle of 26 and take the remainder. Wrap errors cluster at the end of the alphabet, which is exactly where questions place them. ### Counting positions from the wrong end Some codes use position from Z rather than from A. If the numbers look mirrored, try 27 minus the position — that single check resolves a family of questions that otherwise look patternless. ## Keep the streak going One puzzle a day, timed on the server, with a national and state leaderboard and a streak that survives as long as you do. Practising a topic once is worth little; the aspirants who move are the ones who show up daily. [See what Deduce does](https://deducepuzzles.com/features) or [read the rules first](https://deducepuzzles.com/how-to-play). ## FAQ ### What is the fastest way to solve coding decoding questions? Write the word and its code one above the other and subtract the alphabet positions column by column. The pattern in those differences is the rule. This takes about fifteen seconds and replaces the guess-and-check approach that makes the topic feel slow. ### Do I need to memorise the alphabet positions? You need six anchors, not twenty-six: A=1, E=5, J=10, O=15, T=20, Y=25. Counting a step or two from the nearest anchor is fast enough for exam conditions and far more reliable than rote-learning the full list. ### What if my rule works on the first word but not the second? Then the rule is wrong, and finding that out is the point of testing it. Go back to the difference row and look for the pattern that explains both. Two words constrain the rule far more tightly than one, which is why sets usually give two. ### How do I handle codes that mix letters and numbers? The numbers are almost always alphabet positions or a simple function of them, such as position plus one or position squared's last digit. Convert every number to the letter it would represent and the mixed code usually collapses into an ordinary letter rule. ## Practise the next topic - [All reasoning topics](https://deducepuzzles.com/reasoning) — the full practice hub. - [Blood relation questions](https://deducepuzzles.com/reasoning/blood-relations) — blood relations practice with worked solutions. - [Classification reasoning questions](https://deducepuzzles.com/reasoning/classification) — classification practice with worked solutions. - [Direction sense questions](https://deducepuzzles.com/reasoning/direction-sense) — direction & distance practice with worked solutions. - [All 28 reasoning puzzle types](https://deducepuzzles.com/reasoning-puzzle-types) — one real example of each. - [SBI reasoning: pattern, topics and a daily routine](https://deducepuzzles.com/sbi) — how to fit this into a study plan. Deduce is not affiliated with IBPS, SBI, SSC or RBI.