0.000 003 66 Converted to 32 Bit Single Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 0.000 003 66(10) to 32 bit single precision IEEE 754 binary floating point representation standard (1 bit for sign, 8 bits for exponent, 23 bits for mantissa)

What are the steps to convert decimal number
0.000 003 66(10) to 32 bit single precision IEEE 754 binary floating point representation (1 bit for sign, 8 bits for exponent, 23 bits for mantissa)

1. First, convert to binary (in base 2) the integer part: 0.
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;
  • 0 ÷ 2 = 0 + 0;

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.

0(10) =


0(2)


3. Convert to binary (base 2) the fractional part: 0.000 003 66.

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) 0.000 003 66 × 2 = 0 + 0.000 007 32;
  • 2) 0.000 007 32 × 2 = 0 + 0.000 014 64;
  • 3) 0.000 014 64 × 2 = 0 + 0.000 029 28;
  • 4) 0.000 029 28 × 2 = 0 + 0.000 058 56;
  • 5) 0.000 058 56 × 2 = 0 + 0.000 117 12;
  • 6) 0.000 117 12 × 2 = 0 + 0.000 234 24;
  • 7) 0.000 234 24 × 2 = 0 + 0.000 468 48;
  • 8) 0.000 468 48 × 2 = 0 + 0.000 936 96;
  • 9) 0.000 936 96 × 2 = 0 + 0.001 873 92;
  • 10) 0.001 873 92 × 2 = 0 + 0.003 747 84;
  • 11) 0.003 747 84 × 2 = 0 + 0.007 495 68;
  • 12) 0.007 495 68 × 2 = 0 + 0.014 991 36;
  • 13) 0.014 991 36 × 2 = 0 + 0.029 982 72;
  • 14) 0.029 982 72 × 2 = 0 + 0.059 965 44;
  • 15) 0.059 965 44 × 2 = 0 + 0.119 930 88;
  • 16) 0.119 930 88 × 2 = 0 + 0.239 861 76;
  • 17) 0.239 861 76 × 2 = 0 + 0.479 723 52;
  • 18) 0.479 723 52 × 2 = 0 + 0.959 447 04;
  • 19) 0.959 447 04 × 2 = 1 + 0.918 894 08;
  • 20) 0.918 894 08 × 2 = 1 + 0.837 788 16;
  • 21) 0.837 788 16 × 2 = 1 + 0.675 576 32;
  • 22) 0.675 576 32 × 2 = 1 + 0.351 152 64;
  • 23) 0.351 152 64 × 2 = 0 + 0.702 305 28;
  • 24) 0.702 305 28 × 2 = 1 + 0.404 610 56;
  • 25) 0.404 610 56 × 2 = 0 + 0.809 221 12;
  • 26) 0.809 221 12 × 2 = 1 + 0.618 442 24;
  • 27) 0.618 442 24 × 2 = 1 + 0.236 884 48;
  • 28) 0.236 884 48 × 2 = 0 + 0.473 768 96;
  • 29) 0.473 768 96 × 2 = 0 + 0.947 537 92;
  • 30) 0.947 537 92 × 2 = 1 + 0.895 075 84;
  • 31) 0.895 075 84 × 2 = 1 + 0.790 151 68;
  • 32) 0.790 151 68 × 2 = 1 + 0.580 303 36;
  • 33) 0.580 303 36 × 2 = 1 + 0.160 606 72;
  • 34) 0.160 606 72 × 2 = 0 + 0.321 213 44;
  • 35) 0.321 213 44 × 2 = 0 + 0.642 426 88;
  • 36) 0.642 426 88 × 2 = 1 + 0.284 853 76;
  • 37) 0.284 853 76 × 2 = 0 + 0.569 707 52;
  • 38) 0.569 707 52 × 2 = 1 + 0.139 415 04;
  • 39) 0.139 415 04 × 2 = 0 + 0.278 830 08;
  • 40) 0.278 830 08 × 2 = 0 + 0.557 660 16;
  • 41) 0.557 660 16 × 2 = 1 + 0.115 320 32;
  • 42) 0.115 320 32 × 2 = 0 + 0.230 640 64;

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:


0.000 003 66(10) =


0.0000 0000 0000 0000 0011 1101 0110 0111 1001 0100 10(2)

5. Positive number before normalization:

0.000 003 66(10) =


0.0000 0000 0000 0000 0011 1101 0110 0111 1001 0100 10(2)

6. Normalize the binary representation of the number.

Shift the decimal mark 19 positions to the right, so that only one non zero digit remains to the left of it:


0.000 003 66(10) =


0.0000 0000 0000 0000 0011 1101 0110 0111 1001 0100 10(2) =


0.0000 0000 0000 0000 0011 1101 0110 0111 1001 0100 10(2) × 20 =


1.1110 1011 0011 1100 1010 010(2) × 2-19


7. Up to this moment, there are the following elements that would feed into the 32 bit single precision IEEE 754 binary floating point representation:

Sign 0 (a positive number)


Exponent (unadjusted): -19


Mantissa (not normalized):
1.1110 1011 0011 1100 1010 010


8. Adjust the exponent.

Use the 8 bit excess/bias notation:


Exponent (adjusted) =


Exponent (unadjusted) + 2(8-1) - 1 =


-19 + 2(8-1) - 1 =


(-19 + 127)(10) =


108(10)


9. Convert the adjusted exponent from the decimal (base 10) to 8 bit binary.

Use the same technique of repeatedly dividing by 2:


  • division = quotient + remainder;
  • 108 ÷ 2 = 54 + 0;
  • 54 ÷ 2 = 27 + 0;
  • 27 ÷ 2 = 13 + 1;
  • 13 ÷ 2 = 6 + 1;
  • 6 ÷ 2 = 3 + 0;
  • 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) =


108(10) =


0110 1100(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 23 bits, only if necessary (not the case here).


Mantissa (normalized) =


1. 111 0101 1001 1110 0101 0010 =


111 0101 1001 1110 0101 0010


12. The three elements that make up the number's 32 bit single precision IEEE 754 binary floating point representation:

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


Exponent (8 bits) =
0110 1100


Mantissa (23 bits) =
111 0101 1001 1110 0101 0010


Decimal number 0.000 003 66 converted to 32 bit single precision IEEE 754 binary floating point representation:

0 - 0110 1100 - 111 0101 1001 1110 0101 0010


How to convert decimal numbers from base ten to 32 bit single precision IEEE 754 binary floating point standard

Follow the steps below to convert a base 10 decimal number to 32 bit single 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 base ten 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 of the previous dividing 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 previous multiplying operations, starting from the top of the constructed list 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, by shifting the decimal point (or if you prefer, the decimal mark) "n" positions either to the left or to the right, so that only one non zero digit remains to the left of the decimal point.
  • 7. Adjust the exponent in 8 bit excess/bias notation and then convert it from decimal (base 10) to 8 bit binary, by using the same technique of repeatedly dividing by 2, as shown above:
    Exponent (adjusted) = Exponent (unadjusted) + 2(8-1) - 1
  • 8. Normalize mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal sign if the case) and adjust its length to 23 bits, either by removing the excess bits from the right (losing precision...) or by adding extra '0' bits 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 -25.347 from decimal system (base ten) to 32 bit single precision IEEE 754 binary floating point:

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

    |-25.347| = 25.347

  • 2. First convert the integer part, 25. Divide it repeatedly by 2, keeping track of each remainder, until we get a quotient that is equal to zero:
    • division = quotient + remainder;
    • 25 ÷ 2 = 12 + 1;
    • 12 ÷ 2 = 6 + 0;
    • 6 ÷ 2 = 3 + 0;
    • 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:

    25(10) = 1 1001(2)

  • 4. Then convert the fractional part, 0.347. 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) 0.347 × 2 = 0 + 0.694;
    • 2) 0.694 × 2 = 1 + 0.388;
    • 3) 0.388 × 2 = 0 + 0.776;
    • 4) 0.776 × 2 = 1 + 0.552;
    • 5) 0.552 × 2 = 1 + 0.104;
    • 6) 0.104 × 2 = 0 + 0.208;
    • 7) 0.208 × 2 = 0 + 0.416;
    • 8) 0.416 × 2 = 0 + 0.832;
    • 9) 0.832 × 2 = 1 + 0.664;
    • 10) 0.664 × 2 = 1 + 0.328;
    • 11) 0.328 × 2 = 0 + 0.656;
    • 12) 0.656 × 2 = 1 + 0.312;
    • 13) 0.312 × 2 = 0 + 0.624;
    • 14) 0.624 × 2 = 1 + 0.248;
    • 15) 0.248 × 2 = 0 + 0.496;
    • 16) 0.496 × 2 = 0 + 0.992;
    • 17) 0.992 × 2 = 1 + 0.984;
    • 18) 0.984 × 2 = 1 + 0.968;
    • 19) 0.968 × 2 = 1 + 0.936;
    • 20) 0.936 × 2 = 1 + 0.872;
    • 21) 0.872 × 2 = 1 + 0.744;
    • 22) 0.744 × 2 = 1 + 0.488;
    • 23) 0.488 × 2 = 0 + 0.976;
    • 24) 0.976 × 2 = 1 + 0.952;
    • We didn't get any fractional part that was equal to zero. But we had enough iterations (over Mantissa limit = 23) 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:

    0.347(10) = 0.0101 1000 1101 0100 1111 1101(2)

  • 6. Summarizing - the positive number before normalization:

    25.347(10) = 1 1001.0101 1000 1101 0100 1111 1101(2)

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

    25.347(10) =
    1 1001.0101 1000 1101 0100 1111 1101(2) =
    1 1001.0101 1000 1101 0100 1111 1101(2) × 20 =
    1.1001 0101 1000 1101 0100 1111 1101(2) × 24

  • 8. Up to this moment, there are the following elements that would feed into the 32 bit single precision IEEE 754 binary floating point:

    Sign: 1 (a negative number)

    Exponent (unadjusted): 4

    Mantissa (not-normalized): 1.1001 0101 1000 1101 0100 1111 1101

  • 9. Adjust the exponent in 8 bit excess/bias notation and then convert it from decimal (base 10) to 8 bit binary (base 2), by using the same technique of repeatedly dividing it by 2, as already demonstrated above:

    Exponent (adjusted) = Exponent (unadjusted) + 2(8-1) - 1 = (4 + 127)(10) = 131(10) =
    1000 0011(2)

  • 10. Normalize the mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal point) and adjust its length to 23 bits, by removing the excess bits from the right (losing precision...):

    Mantissa (not-normalized): 1.1001 0101 1000 1101 0100 1111 1101

    Mantissa (normalized): 100 1010 1100 0110 1010 0111

  • Conclusion:

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

    Exponent (8 bits) = 1000 0011

    Mantissa (23 bits) = 100 1010 1100 0110 1010 0111

  • Number -25.347, converted from the decimal system (base 10) to 32 bit single precision IEEE 754 binary floating point =
    1 - 1000 0011 - 100 1010 1100 0110 1010 0111