0.000 003 72 Converted to 32 Bit Single Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 0.000 003 72(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 72(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 72.

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 72 × 2 = 0 + 0.000 007 44;
  • 2) 0.000 007 44 × 2 = 0 + 0.000 014 88;
  • 3) 0.000 014 88 × 2 = 0 + 0.000 029 76;
  • 4) 0.000 029 76 × 2 = 0 + 0.000 059 52;
  • 5) 0.000 059 52 × 2 = 0 + 0.000 119 04;
  • 6) 0.000 119 04 × 2 = 0 + 0.000 238 08;
  • 7) 0.000 238 08 × 2 = 0 + 0.000 476 16;
  • 8) 0.000 476 16 × 2 = 0 + 0.000 952 32;
  • 9) 0.000 952 32 × 2 = 0 + 0.001 904 64;
  • 10) 0.001 904 64 × 2 = 0 + 0.003 809 28;
  • 11) 0.003 809 28 × 2 = 0 + 0.007 618 56;
  • 12) 0.007 618 56 × 2 = 0 + 0.015 237 12;
  • 13) 0.015 237 12 × 2 = 0 + 0.030 474 24;
  • 14) 0.030 474 24 × 2 = 0 + 0.060 948 48;
  • 15) 0.060 948 48 × 2 = 0 + 0.121 896 96;
  • 16) 0.121 896 96 × 2 = 0 + 0.243 793 92;
  • 17) 0.243 793 92 × 2 = 0 + 0.487 587 84;
  • 18) 0.487 587 84 × 2 = 0 + 0.975 175 68;
  • 19) 0.975 175 68 × 2 = 1 + 0.950 351 36;
  • 20) 0.950 351 36 × 2 = 1 + 0.900 702 72;
  • 21) 0.900 702 72 × 2 = 1 + 0.801 405 44;
  • 22) 0.801 405 44 × 2 = 1 + 0.602 810 88;
  • 23) 0.602 810 88 × 2 = 1 + 0.205 621 76;
  • 24) 0.205 621 76 × 2 = 0 + 0.411 243 52;
  • 25) 0.411 243 52 × 2 = 0 + 0.822 487 04;
  • 26) 0.822 487 04 × 2 = 1 + 0.644 974 08;
  • 27) 0.644 974 08 × 2 = 1 + 0.289 948 16;
  • 28) 0.289 948 16 × 2 = 0 + 0.579 896 32;
  • 29) 0.579 896 32 × 2 = 1 + 0.159 792 64;
  • 30) 0.159 792 64 × 2 = 0 + 0.319 585 28;
  • 31) 0.319 585 28 × 2 = 0 + 0.639 170 56;
  • 32) 0.639 170 56 × 2 = 1 + 0.278 341 12;
  • 33) 0.278 341 12 × 2 = 0 + 0.556 682 24;
  • 34) 0.556 682 24 × 2 = 1 + 0.113 364 48;
  • 35) 0.113 364 48 × 2 = 0 + 0.226 728 96;
  • 36) 0.226 728 96 × 2 = 0 + 0.453 457 92;
  • 37) 0.453 457 92 × 2 = 0 + 0.906 915 84;
  • 38) 0.906 915 84 × 2 = 1 + 0.813 831 68;
  • 39) 0.813 831 68 × 2 = 1 + 0.627 663 36;
  • 40) 0.627 663 36 × 2 = 1 + 0.255 326 72;
  • 41) 0.255 326 72 × 2 = 0 + 0.510 653 44;
  • 42) 0.510 653 44 × 2 = 1 + 0.021 306 88;

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 72(10) =


0.0000 0000 0000 0000 0011 1110 0110 1001 0100 0111 01(2)

5. Positive number before normalization:

0.000 003 72(10) =


0.0000 0000 0000 0000 0011 1110 0110 1001 0100 0111 01(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 72(10) =


0.0000 0000 0000 0000 0011 1110 0110 1001 0100 0111 01(2) =


0.0000 0000 0000 0000 0011 1110 0110 1001 0100 0111 01(2) × 20 =


1.1111 0011 0100 1010 0011 101(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):
1.1111 0011 0100 1010 0011 101


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 1001 1010 0101 0001 1101 =


111 1001 1010 0101 0001 1101


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 1001 1010 0101 0001 1101


Decimal number 0.000 003 72 converted to 32 bit single precision IEEE 754 binary floating point representation:

0 - 0110 1100 - 111 1001 1010 0101 0001 1101


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