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

How to convert 1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 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
1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000(2) to a base 10 decimal system equivalent integer?

1. Is this a positive or a negative number?

1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000 is the binary representation of a negative 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:


1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000 = 001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 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

    1
  • 259

    1
  • 258

    0
  • 257

    0
  • 256

    0
  • 255

    0
  • 254

    1
  • 253

    1
  • 252

    1
  • 251

    0
  • 250

    1
  • 249

    1
  • 248

    0
  • 247

    0
  • 246

    1
  • 245

    0
  • 244

    1
  • 243

    0
  • 242

    1
  • 241

    0
  • 240

    0
  • 239

    0
  • 238

    0
  • 237

    1
  • 236

    1
  • 235

    0
  • 234

    0
  • 233

    1
  • 232

    0
  • 231

    0
  • 230

    0
  • 229

    0
  • 228

    1
  • 227

    0
  • 226

    0
  • 225

    0
  • 224

    0
  • 223

    0
  • 222

    1
  • 221

    0
  • 220

    1
  • 219

    0
  • 218

    1
  • 217

    0
  • 216

    0
  • 215

    0
  • 214

    0
  • 213

    1
  • 212

    1
  • 211

    0
  • 210

    0
  • 29

    1
  • 28

    0
  • 27

    0
  • 26

    0
  • 25

    0
  • 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.

001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000(2) =


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


(0 + 0 + 1 152 921 504 606 846 976 + 576 460 752 303 423 488 + 0 + 0 + 0 + 0 + 18 014 398 509 481 984 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 0 + 1 125 899 906 842 624 + 562 949 953 421 312 + 0 + 0 + 70 368 744 177 664 + 0 + 17 592 186 044 416 + 0 + 4 398 046 511 104 + 0 + 0 + 0 + 0 + 137 438 953 472 + 68 719 476 736 + 0 + 0 + 8 589 934 592 + 0 + 0 + 0 + 0 + 268 435 456 + 0 + 0 + 0 + 0 + 0 + 4 194 304 + 0 + 1 048 576 + 0 + 262 144 + 0 + 0 + 0 + 0 + 8 192 + 4 096 + 0 + 0 + 512 + 0 + 0 + 0 + 0 + 0 + 8 + 0 + 0 + 0)(10) =


(1 152 921 504 606 846 976 + 576 460 752 303 423 488 + 18 014 398 509 481 984 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 1 125 899 906 842 624 + 562 949 953 421 312 + 70 368 744 177 664 + 17 592 186 044 416 + 4 398 046 511 104 + 137 438 953 472 + 68 719 476 736 + 8 589 934 592 + 268 435 456 + 4 194 304 + 1 048 576 + 262 144 + 8 192 + 4 096 + 512 + 8)(10) =


1 762 688 878 161 179 144(10)

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

1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000(2) = -1 762 688 878 161 179 144(10)

1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000(2), Base 2 signed binary number, converted and written as a base 10 decimal system equivalent integer:
1001 1000 0111 0110 0101 0100 0011 0010 0001 0000 0101 0100 0011 0010 0000 1000(2) = -1 762 688 878 161 179 144(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