Long Multiplication Calculator
Multiply large numbers using the long multiplication column method — with full step-by-step working shown. Each digit is multiplied separately and the partial products are added together.
246 × 37
9102
How it works
Set up long multiplication
Multiply 246 by each digit of 37 separately, starting from the units digit. Each row shifts one place to the left.
Multiply by 7 (units)
246 × 7 = 1722.
Result:1722Multiply by 3 (tens digit)
246 × 3 = 738. As this is the tens digit, the row value is 7380.
Result:7380Add the rows together
Add all the partial products: 1722 + 7380 = 9102.
Result:9102
The formula
Example substitution
Multiply by units digit (7), then tens digit (3, shifted left), then add the rows.
Worked examples
Calculate 47 × 23 using long multiplication.
- 147 × 3: = 141 (units)
- 247 × 20: = 940 (tens, shift left)
- 3Add rows: 141 + 940 = 1081
Calculate 135 × 24 using long multiplication.
- 1135 × 4: = 540
- 2135 × 20: = 2700
- 3Add rows: 540 + 2700 = 3240
Calculate 246 × 37 using long multiplication.
- 1246 × 7: = 1722
- 2246 × 30: = 7380
- 3Add rows: 1722 + 7380 = 9102
Frequently asked questions
How do you do long multiplication?+
Multiply the top number by each digit of the bottom number in turn, shifting one place left for each row, then add all the rows.
What is 347 × 28?+
347 × 28: 347×8 = 2776; 347×20 = 6940; total = 9716.
What is the grid method?+
Split each number into hundreds, tens and units, multiply each combination in a grid, then add the results.
When do you use long multiplication?+
When multiplying numbers too large for mental arithmetic, especially numbers with 2 or more digits each.