Long Multiplication Calculator

Solve complex multiplication problems with ease. This tool breaks down the multiplication process into its individual partial products, showing you how the final result is built.

Product = Multiplicand × Multiplier
123 × 45: • 123 × 5 = 615 • 123 × 40 = 4,920 • Sum = 5,535.

What is long multiplication?

Long multiplication is a standard algorithm for multiplying large numbers. It involves multiplying the multiplicand by each digit of the multiplier, creating "partial products," and then summing those products to find the final total.

What are the parts of a multiplication problem?

The first number is the "Multiplicand," the second number is the "Multiplier," and the final result is called the "Product."

Why do we add a zero in each new row of long multiplication?

The zero (or placeholder) is added because each new digit in the multiplier represents a higher power of 10 (tens, hundreds, etc.). Multiplying by the second digit is actually multiplying by that digit times 10.

Can I multiply decimals with this method?

Yes. To multiply decimals, multiply them as if they were whole numbers, then count the total number of decimal places in both original numbers and place the decimal point in the product so it has the same number of places.