Convert 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000 Base 2 Signed Binary Number on 64 Bit - To Base 10 Decimal System Integer

How to convert 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2), the base 2 signed binary number on 64 bit, to a base 10 decimal system integer

What are the steps to convert the base 2 signed binary number
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) to a base 10 decimal system equivalent integer?

1. Is this a positive or a negative number?

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000 is the binary representation of a positive integer, on 64 bits (8 Bytes).


  • In a signed binary, the first bit (the leftmost) is reserved for the sign, 1 = negative, 0 = positive. This bit does not count when calculating the absolute value.

2. Construct the unsigned binary number.

Exclude the first bit (the leftmost), that is reserved for the sign:


0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000 = 000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000


3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:

  • 262

    0
  • 261

    0
  • 260

    0
  • 259

    0
  • 258

    0
  • 257

    0
  • 256

    1
  • 255

    0
  • 254

    0
  • 253

    1
  • 252

    0
  • 251

    0
  • 250

    0
  • 249

    1
  • 248

    1
  • 247

    0
  • 246

    1
  • 245

    0
  • 244

    0
  • 243

    0
  • 242

    1
  • 241

    0
  • 240

    1
  • 239

    0
  • 238

    1
  • 237

    1
  • 236

    0
  • 235

    0
  • 234

    1
  • 233

    1
  • 232

    1
  • 231

    1
  • 230

    0
  • 229

    0
  • 228

    0
  • 227

    1
  • 226

    0
  • 225

    0
  • 224

    1
  • 223

    1
  • 222

    0
  • 221

    1
  • 220

    0
  • 219

    1
  • 218

    0
  • 217

    1
  • 216

    1
  • 215

    1
  • 214

    1
  • 213

    0
  • 212

    0
  • 211

    1
  • 210

    1
  • 29

    0
  • 28

    1
  • 27

    1
  • 26

    1
  • 25

    1
  • 24

    0
  • 23

    1
  • 22

    0
  • 21

    0
  • 20

    0

4. Multiply each bit by its corresponding power of 2 and add all the terms up.

000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) =


(0 × 262 + 0 × 261 + 0 × 260 + 0 × 259 + 0 × 258 + 0 × 257 + 1 × 256 + 0 × 255 + 0 × 254 + 1 × 253 + 0 × 252 + 0 × 251 + 0 × 250 + 1 × 249 + 1 × 248 + 0 × 247 + 1 × 246 + 0 × 245 + 0 × 244 + 0 × 243 + 1 × 242 + 0 × 241 + 1 × 240 + 0 × 239 + 1 × 238 + 1 × 237 + 0 × 236 + 0 × 235 + 1 × 234 + 1 × 233 + 1 × 232 + 1 × 231 + 0 × 230 + 0 × 229 + 0 × 228 + 1 × 227 + 0 × 226 + 0 × 225 + 1 × 224 + 1 × 223 + 0 × 222 + 1 × 221 + 0 × 220 + 1 × 219 + 0 × 218 + 1 × 217 + 1 × 216 + 1 × 215 + 1 × 214 + 0 × 213 + 0 × 212 + 1 × 211 + 1 × 210 + 0 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 0 × 24 + 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20)(10) =


(0 + 0 + 0 + 0 + 0 + 0 + 72 057 594 037 927 936 + 0 + 0 + 9 007 199 254 740 992 + 0 + 0 + 0 + 562 949 953 421 312 + 281 474 976 710 656 + 0 + 70 368 744 177 664 + 0 + 0 + 0 + 4 398 046 511 104 + 0 + 1 099 511 627 776 + 0 + 274 877 906 944 + 137 438 953 472 + 0 + 0 + 17 179 869 184 + 8 589 934 592 + 4 294 967 296 + 2 147 483 648 + 0 + 0 + 0 + 134 217 728 + 0 + 0 + 16 777 216 + 8 388 608 + 0 + 2 097 152 + 0 + 524 288 + 0 + 131 072 + 65 536 + 32 768 + 16 384 + 0 + 0 + 2 048 + 1 024 + 0 + 256 + 128 + 64 + 32 + 0 + 8 + 0 + 0 + 0)(10) =


(72 057 594 037 927 936 + 9 007 199 254 740 992 + 562 949 953 421 312 + 281 474 976 710 656 + 70 368 744 177 664 + 4 398 046 511 104 + 1 099 511 627 776 + 274 877 906 944 + 137 438 953 472 + 17 179 869 184 + 8 589 934 592 + 4 294 967 296 + 2 147 483 648 + 134 217 728 + 16 777 216 + 8 388 608 + 2 097 152 + 524 288 + 131 072 + 65 536 + 32 768 + 16 384 + 2 048 + 1 024 + 256 + 128 + 64 + 32 + 8)(10) =


81 985 529 216 486 888(10)

5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) = 81 985 529 216 486 888(10)

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2), Base 2 signed binary number, converted and written as a base 10 decimal system equivalent integer:
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) = 81 985 529 216 486 888(10)

Spaces were used to group digits: for binary, by 4, for decimal, by 3.


How to convert signed binary numbers from binary system to decimal (base ten)

To understand how to convert a signed binary number from binary system to decimal (base ten), the easiest way is to do it through an example - convert the binary number, 1001 1110, to base ten:

  • In a signed binary, the first bit (leftmost) is reserved for the sign, 1 = negative, 0 = positive. This bit does not count when calculating the absolute value (value without sign). The first bit is 1, so our number is negative.
  • Write bellow the binary number in base two, and above each bit that makes up the binary number write the corresponding power of 2 (numeral base) that its place value represents, starting with zero, from the right of the number (rightmost bit), walking to the left of the number and increasing each corresonding power of 2 by exactly one unit, but ignoring the very first bit (the leftmost, the one representing the sign):
  • powers of 2:   6 5 4 3 2 1 0
    digits: 1 0 0 1 1 1 1 0
  • Build the representation of the positive number in base 10, by taking each digit of the binary number, multiplying it by the corresponding power of 2 and then adding all the terms up, but also taking care of the number sign:

    1001 1110 =


    - (0 × 26 + 0 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 0 × 20)(10) =


    - (0 + 0 + 16 + 8 + 4 + 2 + 0)(10) =


    - (16 + 8 + 4 + 2)(10) =


    -30(10)

  • Binary signed number, 1001 1110 = -30(10), signed negative integer in base 10