What is the Vedic Rectangle (Box) Multiplication Calculator?
This tool multiplies two numbers and shows the answer the "rectangle" or "box method" way used in Indian and Vedic mental-math training. Instead of a single column multiplication, the digits of each number are laid out along the sides of a rectangle, and the area of each cell becomes a partial product. Adding the partial products gives the final answer. The headline result is just the ordinary product A times B, so it works for any numbers; the grid breakdown is a learning aid for two-digit non-negative integers.
How to use it
Enter the first number A and the second number B, then read the Answer. If both numbers are non-negative integers, a table appears showing the four cell products and their place values, so you can see exactly how the total is built up. This trains you to do the same decomposition in your head.
The formula explained
Write A as 10· a_1 + a_0 and B as 10· b_1 + b_0, where a_1, b_1 are the tens digits and a_0, b_0 are the ones digits. The rectangle has four cells whose areas are a_1· b_1, a_1· b_0, a_0· b_1 and a_0· b_0. Scaling by place value:
More generally:
Worked example
For 44 × 36: a_1=4, a_0=4, b_1=3, b_0=6. Cells: 4· 3=12 (× 100 = 1200), 4· 6=24 (× 10 = 240), 4· 3=12 (× 10 = 120), 4· 6=24 (× 1 = 24). Sum =
which equals 44 × 36.
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