21001 octal to binary

Here we will show you how to convert the octal number 21001 to a binary number. First note that the octal number system has eight different digits (0 1 2 3 4 5 6 7) and the binary number system has only two different digits (0 and 1).

The four steps used to convert 21001 from octal to binary are explained below.

Step 1)
Multiply the last digit in 21001 by 8⁰, multiply the second to last digit in 21001 by 8¹, multiply the third to last digit in 21001 by 8², multiply the fourth to last digit in 21001 by 8³, and so on, until all the digits are used:

1 × 8⁰ = 1
0 × 8¹ = 0
0 × 8² = 0
1 × 8³ = 512
2 × 8⁴ = 8192

Step 2)
Next, we add up all the products we got from Step 1, like this:

1 + 0 + 0 + 512 + 8192 = 8705

Step 3)
Now we divide the sum from Step 2 by 2. Put the remainder aside. Then divide the whole part by 2 again, and put the remainder aside again. Keep doing this until the whole part is 0.

8705 ÷ 2 = 4352 with 1 remainder
4352 ÷ 2 = 2176 with 0 remainder
2176 ÷ 2 = 1088 with 0 remainder
1088 ÷ 2 = 544 with 0 remainder
544 ÷ 2 = 272 with 0 remainder
272 ÷ 2 = 136 with 0 remainder
136 ÷ 2 = 68 with 0 remainder
68 ÷ 2 = 34 with 0 remainder
34 ÷ 2 = 17 with 0 remainder
17 ÷ 2 = 8 with 1 remainder
8 ÷ 2 = 4 with 0 remainder
4 ÷ 2 = 2 with 0 remainder
2 ÷ 2 = 1 with 0 remainder
1 ÷ 2 = 0 with 1 remainder

Step 4)
In the final step, we take the remainders from Step 3 and put them together in reverse order to get our answer to 21001 octal to binary:

21001 octal = 10001000000001 binary

Octal to Binary Converter
Here you can convert another octal number to binary. Remember, octal numbers only include digits 0 through 7.

21002 octal to binary
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