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Long Division (Step-by-Step) Calculator

Long division breaks a division problem into a repeated cycle of four steps — divide, multiply, subtract, bring down — worked one digit at a time from left to right. This calculator shows the full working, not just the final quotient, specifically for anyone re-learning the manual method or checking their own work against it.

Worked Example: 936 ÷ 4

Take 936 ÷ 4 as a worked example. First digit: 4 fits into 9 twice, with some left over (4 × 2 = 8, remainder 1). Bring the next digit (3) down alongside that remainder to make 13; 4 fits into 13 three times (4 × 3 = 12, remainder 1). Bring down the last digit (6) to make 16; 4 fits into 16 exactly four times, with nothing left over. Stringing together each step's answer — 2, then 3, then 4 — gives 936 ÷ 4 = 234, no remainder.

A second worked example, this time with a remainder: 179 ÷ 5. 5 goes into 17 three times (5×3=15), subtract to get 2, bring down 9 to make 29. 5 goes into 29 five times (5×5=25), subtract to get 4, nothing left to bring down. Quotient so far: 35, remainder 4. Written as a mixed result, that's 179 ÷ 5 = 35 remainder 4 — or, if you keep going instead of stopping, tack a zero onto the remainder to get 40, and 5 divides evenly into that eight times, landing on 35.8 with nothing left over.

The "bring down a zero and continue" step is exactly how a remainder becomes a decimal continuation instead of stopping at "remainder 4" — you're not doing anything fundamentally different, just continuing the same divide-multiply-subtract-bring-down cycle into the decimal places, and it can continue indefinitely if the division doesn't terminate cleanly (dividing by 3, for instance, often produces a repeating decimal).

Worked Example: a Two-Digit Divisor, 483 ÷ 21

483 ÷ 21. 21 doesn't go into 4 or 48 alone at the single-digit level the same way, so you work with the first two digits: 21 goes into 48 twice (21×2=42), subtract to get 6, bring down 3 to make 63. 21 goes into 63 exactly three times (21×3=63), subtract to get 0. Quotient: 23, no remainder. The four-step cycle doesn't change once the divisor grows past a single digit — the only real difference is that guessing how many times a two-digit divisor fits takes a bit more trial and error than pulling a memorized single-digit fact.

Common Mistakes in Long Division

A common mistake is misaligning the digits as they're written down — each step's answer needs to land in the correct place-value column, and a slip here quietly shifts the final decimal point by a power of 10 without changing any of the individual arithmetic. A second common mistake shows up in the "how many times does it fit" guess at each stage: guess too high and the subtraction goes negative, guess too low and what's left over is still bigger than the divisor — either outcome is an unambiguous signal to walk that particular step back and try a different guess.

Long division is also the mechanical process underneath the "decimal doesn't terminate" fact discussed on the Fraction to Decimal Converter — dividing 1 by 3 by hand, you'll notice the remainder at each step (1, then 10, then 1 again) starts repeating, which is exactly why 1/3 = 0.333... repeats forever rather than settling to zero: the division process itself has entered a loop, mechanically guaranteed to repeat once a remainder reappears that's already occurred earlier in the same division.

The dedicated long-division guide covers this same territory with additional worked examples, including more two-digit-divisor practice.