1.797 693 134 73 Converted to 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 1.797 693 134 73(10) to 64 bit double precision IEEE 754 binary floating point representation standard (1 bit for sign, 11 bits for exponent, 52 bits for mantissa)

What are the steps to convert decimal number
1.797 693 134 73(10) to 64 bit double precision IEEE 754 binary floating point representation (1 bit for sign, 11 bits for exponent, 52 bits for mantissa)

1. First, convert to binary (in base 2) the integer part: 1.
Divide the number repeatedly by 2.

Keep track of each remainder.

We stop when we get a quotient that is equal to zero.


  • division = quotient + remainder;
  • 1 ÷ 2 = 0 + 1;

2. Construct the base 2 representation of the integer part of the number.

Take all the remainders starting from the bottom of the list constructed above.

1(10) =


1(2)


3. Convert to binary (base 2) the fractional part: 0.797 693 134 73.

Multiply it repeatedly by 2.


Keep track of each integer part of the results.


Stop when we get a fractional part that is equal to zero.


  • #) multiplying = integer + fractional part;
  • 1) 0.797 693 134 73 × 2 = 1 + 0.595 386 269 46;
  • 2) 0.595 386 269 46 × 2 = 1 + 0.190 772 538 92;
  • 3) 0.190 772 538 92 × 2 = 0 + 0.381 545 077 84;
  • 4) 0.381 545 077 84 × 2 = 0 + 0.763 090 155 68;
  • 5) 0.763 090 155 68 × 2 = 1 + 0.526 180 311 36;
  • 6) 0.526 180 311 36 × 2 = 1 + 0.052 360 622 72;
  • 7) 0.052 360 622 72 × 2 = 0 + 0.104 721 245 44;
  • 8) 0.104 721 245 44 × 2 = 0 + 0.209 442 490 88;
  • 9) 0.209 442 490 88 × 2 = 0 + 0.418 884 981 76;
  • 10) 0.418 884 981 76 × 2 = 0 + 0.837 769 963 52;
  • 11) 0.837 769 963 52 × 2 = 1 + 0.675 539 927 04;
  • 12) 0.675 539 927 04 × 2 = 1 + 0.351 079 854 08;
  • 13) 0.351 079 854 08 × 2 = 0 + 0.702 159 708 16;
  • 14) 0.702 159 708 16 × 2 = 1 + 0.404 319 416 32;
  • 15) 0.404 319 416 32 × 2 = 0 + 0.808 638 832 64;
  • 16) 0.808 638 832 64 × 2 = 1 + 0.617 277 665 28;
  • 17) 0.617 277 665 28 × 2 = 1 + 0.234 555 330 56;
  • 18) 0.234 555 330 56 × 2 = 0 + 0.469 110 661 12;
  • 19) 0.469 110 661 12 × 2 = 0 + 0.938 221 322 24;
  • 20) 0.938 221 322 24 × 2 = 1 + 0.876 442 644 48;
  • 21) 0.876 442 644 48 × 2 = 1 + 0.752 885 288 96;
  • 22) 0.752 885 288 96 × 2 = 1 + 0.505 770 577 92;
  • 23) 0.505 770 577 92 × 2 = 1 + 0.011 541 155 84;
  • 24) 0.011 541 155 84 × 2 = 0 + 0.023 082 311 68;
  • 25) 0.023 082 311 68 × 2 = 0 + 0.046 164 623 36;
  • 26) 0.046 164 623 36 × 2 = 0 + 0.092 329 246 72;
  • 27) 0.092 329 246 72 × 2 = 0 + 0.184 658 493 44;
  • 28) 0.184 658 493 44 × 2 = 0 + 0.369 316 986 88;
  • 29) 0.369 316 986 88 × 2 = 0 + 0.738 633 973 76;
  • 30) 0.738 633 973 76 × 2 = 1 + 0.477 267 947 52;
  • 31) 0.477 267 947 52 × 2 = 0 + 0.954 535 895 04;
  • 32) 0.954 535 895 04 × 2 = 1 + 0.909 071 790 08;
  • 33) 0.909 071 790 08 × 2 = 1 + 0.818 143 580 16;
  • 34) 0.818 143 580 16 × 2 = 1 + 0.636 287 160 32;
  • 35) 0.636 287 160 32 × 2 = 1 + 0.272 574 320 64;
  • 36) 0.272 574 320 64 × 2 = 0 + 0.545 148 641 28;
  • 37) 0.545 148 641 28 × 2 = 1 + 0.090 297 282 56;
  • 38) 0.090 297 282 56 × 2 = 0 + 0.180 594 565 12;
  • 39) 0.180 594 565 12 × 2 = 0 + 0.361 189 130 24;
  • 40) 0.361 189 130 24 × 2 = 0 + 0.722 378 260 48;
  • 41) 0.722 378 260 48 × 2 = 1 + 0.444 756 520 96;
  • 42) 0.444 756 520 96 × 2 = 0 + 0.889 513 041 92;
  • 43) 0.889 513 041 92 × 2 = 1 + 0.779 026 083 84;
  • 44) 0.779 026 083 84 × 2 = 1 + 0.558 052 167 68;
  • 45) 0.558 052 167 68 × 2 = 1 + 0.116 104 335 36;
  • 46) 0.116 104 335 36 × 2 = 0 + 0.232 208 670 72;
  • 47) 0.232 208 670 72 × 2 = 0 + 0.464 417 341 44;
  • 48) 0.464 417 341 44 × 2 = 0 + 0.928 834 682 88;
  • 49) 0.928 834 682 88 × 2 = 1 + 0.857 669 365 76;
  • 50) 0.857 669 365 76 × 2 = 1 + 0.715 338 731 52;
  • 51) 0.715 338 731 52 × 2 = 1 + 0.430 677 463 04;
  • 52) 0.430 677 463 04 × 2 = 0 + 0.861 354 926 08;
  • 53) 0.861 354 926 08 × 2 = 1 + 0.722 709 852 16;

We didn't get any fractional part that was equal to zero. But we had enough iterations (over Mantissa limit) and at least one integer that was different from zero => FULL STOP (Losing precision - the converted number we get in the end will be just a very good approximation of the initial one).


4. Construct the base 2 representation of the fractional part of the number.

Take all the integer parts of the multiplying operations, starting from the top of the constructed list above:


0.797 693 134 73(10) =


0.1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1(2)

5. Positive number before normalization:

1.797 693 134 73(10) =


1.1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1(2)

6. Normalize the binary representation of the number.

Shift the decimal mark 0 positions to the left, so that only one non zero digit remains to the left of it:


1.797 693 134 73(10) =


1.1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1(2) =


1.1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1(2) × 20


7. Up to this moment, there are the following elements that would feed into the 64 bit double precision IEEE 754 binary floating point representation:

Sign 0 (a positive number)


Exponent (unadjusted): 0


Mantissa (not normalized):
1.1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1


8. Adjust the exponent.

Use the 11 bit excess/bias notation:


Exponent (adjusted) =


Exponent (unadjusted) + 2(11-1) - 1 =


0 + 2(11-1) - 1 =


(0 + 1 023)(10) =


1 023(10)


9. Convert the adjusted exponent from the decimal (base 10) to 11 bit binary.

Use the same technique of repeatedly dividing by 2:


  • division = quotient + remainder;
  • 1 023 ÷ 2 = 511 + 1;
  • 511 ÷ 2 = 255 + 1;
  • 255 ÷ 2 = 127 + 1;
  • 127 ÷ 2 = 63 + 1;
  • 63 ÷ 2 = 31 + 1;
  • 31 ÷ 2 = 15 + 1;
  • 15 ÷ 2 = 7 + 1;
  • 7 ÷ 2 = 3 + 1;
  • 3 ÷ 2 = 1 + 1;
  • 1 ÷ 2 = 0 + 1;

10. Construct the base 2 representation of the adjusted exponent.

Take all the remainders starting from the bottom of the list constructed above.


Exponent (adjusted) =


1023(10) =


011 1111 1111(2)


11. Normalize the mantissa.

a) Remove the leading (the leftmost) bit, since it's allways 1, and the decimal point, if the case.


b) Adjust its length to 52 bits, by removing the excess bits, from the right (if any of the excess bits is set on 1, we are losing precision...).


Mantissa (normalized) =


1. 1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110 1 =


1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110


12. The three elements that make up the number's 64 bit double precision IEEE 754 binary floating point representation:

Sign (1 bit) =
0 (a positive number)


Exponent (11 bits) =
011 1111 1111


Mantissa (52 bits) =
1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110


Decimal number 1.797 693 134 73 converted to 64 bit double precision IEEE 754 binary floating point representation:

0 - 011 1111 1111 - 1100 1100 0011 0101 1001 1110 0000 0101 1110 1000 1011 1000 1110

How to convert numbers from the decimal system (base ten) to 64 bit double precision IEEE 754 binary floating point standard

Follow the steps below to convert a base 10 decimal number to 64 bit double precision IEEE 754 binary floating point:

  • 1. If the number to be converted is negative, start with its the positive version.
  • 2. First convert the integer part. Divide repeatedly by 2 the positive representation of the integer number that is to be converted to binary, until we get a quotient that is equal to zero, keeping track of each remainder.
  • 3. Construct the base 2 representation of the positive integer part of the number, by taking all the remainders from the previous operations, starting from the bottom of the list constructed above. Thus, the last remainder of the divisions becomes the first symbol (the leftmost) of the base two number, while the first remainder becomes the last symbol (the rightmost).
  • 4. Then convert the fractional part. Multiply the number repeatedly by 2, until we get a fractional part that is equal to zero, keeping track of each integer part of the results.
  • 5. Construct the base 2 representation of the fractional part of the number, by taking all the integer parts of the multiplying operations, starting from the top of the list constructed above (they should appear in the binary representation, from left to right, in the order they have been calculated).
  • 6. Normalize the binary representation of the number, shifting the decimal mark (the decimal point) "n" positions either to the left, or to the right, so that only one non zero digit remains to the left of the decimal mark.
  • 7. Adjust the exponent in 11 bit excess/bias notation and then convert it from decimal (base 10) to 11 bit binary, by using the same technique of repeatedly dividing by 2, as shown above:
    Exponent (adjusted) = Exponent (unadjusted) + 2(11-1) - 1
  • 8. Normalize mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal mark, if the case) and adjust its length to 52 bits, either by removing the excess bits from the right (losing precision...) or by adding extra bits set on '0' to the right.
  • 9. Sign (it takes 1 bit) is either 1 for a negative or 0 for a positive number.

Example: convert the negative number -31.640 215 from the decimal system (base ten) to 64 bit double precision IEEE 754 binary floating point:

  • 1. Start with the positive version of the number:

    |-31.640 215| = 31.640 215

  • 2. First convert the integer part, 31. Divide it repeatedly by 2, keeping track of each remainder, until we get a quotient that is equal to zero:
    • division = quotient + remainder;
    • 31 ÷ 2 = 15 + 1;
    • 15 ÷ 2 = 7 + 1;
    • 7 ÷ 2 = 3 + 1;
    • 3 ÷ 2 = 1 + 1;
    • 1 ÷ 2 = 0 + 1;
    • We have encountered a quotient that is ZERO => FULL STOP
  • 3. Construct the base 2 representation of the integer part of the number by taking all the remainders of the previous dividing operations, starting from the bottom of the list constructed above:

    31(10) = 1 1111(2)

  • 4. Then, convert the fractional part, 0.640 215. Multiply repeatedly by 2, keeping track of each integer part of the results, until we get a fractional part that is equal to zero:
    • #) multiplying = integer + fractional part;
    • 1) 0.640 215 × 2 = 1 + 0.280 43;
    • 2) 0.280 43 × 2 = 0 + 0.560 86;
    • 3) 0.560 86 × 2 = 1 + 0.121 72;
    • 4) 0.121 72 × 2 = 0 + 0.243 44;
    • 5) 0.243 44 × 2 = 0 + 0.486 88;
    • 6) 0.486 88 × 2 = 0 + 0.973 76;
    • 7) 0.973 76 × 2 = 1 + 0.947 52;
    • 8) 0.947 52 × 2 = 1 + 0.895 04;
    • 9) 0.895 04 × 2 = 1 + 0.790 08;
    • 10) 0.790 08 × 2 = 1 + 0.580 16;
    • 11) 0.580 16 × 2 = 1 + 0.160 32;
    • 12) 0.160 32 × 2 = 0 + 0.320 64;
    • 13) 0.320 64 × 2 = 0 + 0.641 28;
    • 14) 0.641 28 × 2 = 1 + 0.282 56;
    • 15) 0.282 56 × 2 = 0 + 0.565 12;
    • 16) 0.565 12 × 2 = 1 + 0.130 24;
    • 17) 0.130 24 × 2 = 0 + 0.260 48;
    • 18) 0.260 48 × 2 = 0 + 0.520 96;
    • 19) 0.520 96 × 2 = 1 + 0.041 92;
    • 20) 0.041 92 × 2 = 0 + 0.083 84;
    • 21) 0.083 84 × 2 = 0 + 0.167 68;
    • 22) 0.167 68 × 2 = 0 + 0.335 36;
    • 23) 0.335 36 × 2 = 0 + 0.670 72;
    • 24) 0.670 72 × 2 = 1 + 0.341 44;
    • 25) 0.341 44 × 2 = 0 + 0.682 88;
    • 26) 0.682 88 × 2 = 1 + 0.365 76;
    • 27) 0.365 76 × 2 = 0 + 0.731 52;
    • 28) 0.731 52 × 2 = 1 + 0.463 04;
    • 29) 0.463 04 × 2 = 0 + 0.926 08;
    • 30) 0.926 08 × 2 = 1 + 0.852 16;
    • 31) 0.852 16 × 2 = 1 + 0.704 32;
    • 32) 0.704 32 × 2 = 1 + 0.408 64;
    • 33) 0.408 64 × 2 = 0 + 0.817 28;
    • 34) 0.817 28 × 2 = 1 + 0.634 56;
    • 35) 0.634 56 × 2 = 1 + 0.269 12;
    • 36) 0.269 12 × 2 = 0 + 0.538 24;
    • 37) 0.538 24 × 2 = 1 + 0.076 48;
    • 38) 0.076 48 × 2 = 0 + 0.152 96;
    • 39) 0.152 96 × 2 = 0 + 0.305 92;
    • 40) 0.305 92 × 2 = 0 + 0.611 84;
    • 41) 0.611 84 × 2 = 1 + 0.223 68;
    • 42) 0.223 68 × 2 = 0 + 0.447 36;
    • 43) 0.447 36 × 2 = 0 + 0.894 72;
    • 44) 0.894 72 × 2 = 1 + 0.789 44;
    • 45) 0.789 44 × 2 = 1 + 0.578 88;
    • 46) 0.578 88 × 2 = 1 + 0.157 76;
    • 47) 0.157 76 × 2 = 0 + 0.315 52;
    • 48) 0.315 52 × 2 = 0 + 0.631 04;
    • 49) 0.631 04 × 2 = 1 + 0.262 08;
    • 50) 0.262 08 × 2 = 0 + 0.524 16;
    • 51) 0.524 16 × 2 = 1 + 0.048 32;
    • 52) 0.048 32 × 2 = 0 + 0.096 64;
    • 53) 0.096 64 × 2 = 0 + 0.193 28;
    • We didn't get any fractional part that was equal to zero. But we had enough iterations (over Mantissa limit = 52) and at least one integer part that was different from zero => FULL STOP (losing precision...).
  • 5. Construct the base 2 representation of the fractional part of the number, by taking all the integer parts of the previous multiplying operations, starting from the top of the constructed list above:

    0.640 215(10) = 0.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2)

  • 6. Summarizing - the positive number before normalization:

    31.640 215(10) = 1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2)

  • 7. Normalize the binary representation of the number, shifting the decimal mark 4 positions to the left so that only one non-zero digit stays to the left of the decimal mark:

    31.640 215(10) =
    1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) =
    1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) × 20 =
    1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) × 24

  • 8. Up to this moment, there are the following elements that would feed into the 64 bit double precision IEEE 754 binary floating point representation:

    Sign: 1 (a negative number)

    Exponent (unadjusted): 4

    Mantissa (not-normalized): 1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0

  • 9. Adjust the exponent in 11 bit excess/bias notation and then convert it from decimal (base 10) to 11 bit binary (base 2), by using the same technique of repeatedly dividing it by 2, as shown above:

    Exponent (adjusted) = Exponent (unadjusted) + 2(11-1) - 1 = (4 + 1023)(10) = 1027(10) =
    100 0000 0011(2)

  • 10. Normalize mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal sign) and adjust its length to 52 bits, by removing the excess bits, from the right (losing precision...):

    Mantissa (not-normalized): 1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0

    Mantissa (normalized): 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100

  • Conclusion:

    Sign (1 bit) = 1 (a negative number)

    Exponent (8 bits) = 100 0000 0011

    Mantissa (52 bits) = 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100

  • Number -31.640 215, converted from decimal system (base 10) to 64 bit double precision IEEE 754 binary floating point =
    1 - 100 0000 0011 - 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100