Math calculator

Free long division calculator

Calculate the quotient and remainder of any integer division — enter a dividend and divisor to see the step-by-step result, updated live, as you type.

InputsLive
Dividend
Divisor
Result
Quotient
3
17 ÷ 5 = 3 remainder 2
Dividend17
Divisor5
Remainder2
Decimal Result3.4

Integer quotient with remainder. Decimal = dividend / divisor.

Results are estimates. Consult a professional.

How it's calculated

How the long division calculator works

Long division breaks a large division problem into a sequence of smaller steps: estimate how many times the divisor fits into a partial dividend, multiply, subtract, bring down the next digit, and repeat. The process yields an integer quotient and remainder, or can be extended to produce a decimal by appending zeros to the dividend and continuing.

Quotient = floor(dividend ÷ divisor)
Remainder = dividend (quotient × divisor)
Decimal: continue dividing the remainder × 10 by divisor for each decimal place
Long division is a standard arithmetic algorithm taught in all primary and secondary curricula; the algorithm is documented in NCTM Principles and Standards for School Mathematics.
Example

Worked example: 153 ÷ 7

Example: 153 ÷ 7 with remainder and as a decimal

Divide 153 by 7. First find the integer quotient and remainder, then extend to a decimal.

Step 1: How many times does 7 fit into 15? → 2 (7 × 2 = 14)
Step 2: 15 14 = 1; bring down 3 → partial remainder 13
Step 3: How many times does 7 fit into 13? → 1 (7 × 1 = 7)
Step 4: 13 7 = 6 → remainder 6
Quotient = 21, Remainder = 6
Verify: 21 × 7 + 6 = 147 + 6 = 153 ✓
Decimal extension: remainder 6 → 60 ÷ 7 = 8 r4 → first decimal digit: 8
40 ÷ 7 = 5 r5 → second decimal digit: 5
50 ÷ 7 = 7 r1 → third decimal digit: 7
153 ÷ 7 ≈ 21.857…
21 remainder 6
153 ÷ 7 = 21 remainder 6. As a decimal: 21.857… (6/7 = 0.857142… repeating).
Quick reference

Division facts with quotient and remainder

These examples cover a range of dividend and divisor sizes. Each shows the full result: quotient, remainder, and the equivalent mixed-number form.

Dividend ÷ DivisorQuotientRemainderAs decimal
17 ÷ 5323.4
100 ÷ 7142≈ 14.286
256 ÷ 832032.0
153 ÷ 7216≈ 21.857
1,000 ÷ 33331≈ 333.333
500 ÷ 17297≈ 29.412
144 ÷ 1212012.0
1,234 ÷ 56222≈ 22.036

Remainders verified by: quotient × divisor + remainder = dividend.

Practical tips

Tips for long division

Long division feels mechanical once you internalise the loop: estimate, multiply, subtract, bring down. These tips smooth out the common sticking points.

  • Estimate with rounding — When the divisor is large, round it to the nearest easy number to find the trial digit. Adjust up or down if the product overshoots or undershoots.
  • Always verify — Multiply quotient × divisor, add the remainder, and check you get the original dividend. This catches arithmetic slips in seconds.
  • Bring down one digit at a time — Never skip digits when bringing down. If the current partial dividend is smaller than the divisor, the next quotient digit is 0 and you bring down another digit.
  • Extending to decimals — After the integer quotient, place a decimal point in the answer and append a zero to the remainder, then continue dividing. Repeat for as many decimal places as needed.
  • Spotting repeating decimals — If the same remainder recurs during the decimal extension, the decimal repeats. For example, 1 ÷ 7 produces remainders 1, 3, 2, 6, 4, 5, 1, … — the 6-digit block 142857 repeats forever.
Accuracy & limits

Accuracy and limitations

Integer quotient and remainder are exact for any whole-number dividend and divisor. Decimal extension is terminated after a fixed number of places, introducing rounding. When the remainder cycle length exceeds the displayed decimal places, the result is truncated rather than shown with an overbar. For exact fractional results, use a fraction calculator that retains the numerator/denominator form.

Glossary

Key terms

The number being divided. In 153 ÷ 7, the dividend is 153.
The number you are dividing by. In 153 ÷ 7, the divisor is 7.
The integer result of division, ignoring the remainder. In 153 ÷ 7, the quotient is 21.
What is left over after dividing as evenly as possible. Always satisfies 0 ≤ remainder < divisor. In 153 ÷ 7, the remainder is 6.
A decimal expansion in which a block of digits repeats indefinitely. For example, 1/7 = 0.142857142857… Shown with an overbar: 0.1̄4̄2̄8̄5̄7̄.
The formal mathematical statement: for integers a and b (b > 0), there exist unique integers q and r such that a = bq + r and 0 ≤ r < b. This is what long division computes.
About

About this calculator

Part of our math calculators suite — explore all calculators.

Questions

Frequently asked questions about the free long division calculator

A long division calculator is a free online tool that helps you calculate quotient and remainder of integer division. Standard division with separate remainder. It runs entirely in your browser with instant results and no sign-up.
JavaScript double-precision floating-point — accurate to about 15-17 significant digits. For arbitrary precision, use the Big Number calculator.
The statistics calculator computes population variance (divides by n). For sample variance, multiply variance by n/(n-1).

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