0.000 002 58 Converted to 32 Bit Single Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 0.000 002 58(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
0.000 002 58(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: 0.000 002 58.

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) 0.000 002 58 × 2 = 0 + 0.000 005 16;
  • 2) 0.000 005 16 × 2 = 0 + 0.000 010 32;
  • 3) 0.000 010 32 × 2 = 0 + 0.000 020 64;
  • 4) 0.000 020 64 × 2 = 0 + 0.000 041 28;
  • 5) 0.000 041 28 × 2 = 0 + 0.000 082 56;
  • 6) 0.000 082 56 × 2 = 0 + 0.000 165 12;
  • 7) 0.000 165 12 × 2 = 0 + 0.000 330 24;
  • 8) 0.000 330 24 × 2 = 0 + 0.000 660 48;
  • 9) 0.000 660 48 × 2 = 0 + 0.001 320 96;
  • 10) 0.001 320 96 × 2 = 0 + 0.002 641 92;
  • 11) 0.002 641 92 × 2 = 0 + 0.005 283 84;
  • 12) 0.005 283 84 × 2 = 0 + 0.010 567 68;
  • 13) 0.010 567 68 × 2 = 0 + 0.021 135 36;
  • 14) 0.021 135 36 × 2 = 0 + 0.042 270 72;
  • 15) 0.042 270 72 × 2 = 0 + 0.084 541 44;
  • 16) 0.084 541 44 × 2 = 0 + 0.169 082 88;
  • 17) 0.169 082 88 × 2 = 0 + 0.338 165 76;
  • 18) 0.338 165 76 × 2 = 0 + 0.676 331 52;
  • 19) 0.676 331 52 × 2 = 1 + 0.352 663 04;
  • 20) 0.352 663 04 × 2 = 0 + 0.705 326 08;
  • 21) 0.705 326 08 × 2 = 1 + 0.410 652 16;
  • 22) 0.410 652 16 × 2 = 0 + 0.821 304 32;
  • 23) 0.821 304 32 × 2 = 1 + 0.642 608 64;
  • 24) 0.642 608 64 × 2 = 1 + 0.285 217 28;
  • 25) 0.285 217 28 × 2 = 0 + 0.570 434 56;
  • 26) 0.570 434 56 × 2 = 1 + 0.140 869 12;
  • 27) 0.140 869 12 × 2 = 0 + 0.281 738 24;
  • 28) 0.281 738 24 × 2 = 0 + 0.563 476 48;
  • 29) 0.563 476 48 × 2 = 1 + 0.126 952 96;
  • 30) 0.126 952 96 × 2 = 0 + 0.253 905 92;
  • 31) 0.253 905 92 × 2 = 0 + 0.507 811 84;
  • 32) 0.507 811 84 × 2 = 1 + 0.015 623 68;
  • 33) 0.015 623 68 × 2 = 0 + 0.031 247 36;
  • 34) 0.031 247 36 × 2 = 0 + 0.062 494 72;
  • 35) 0.062 494 72 × 2 = 0 + 0.124 989 44;
  • 36) 0.124 989 44 × 2 = 0 + 0.249 978 88;
  • 37) 0.249 978 88 × 2 = 0 + 0.499 957 76;
  • 38) 0.499 957 76 × 2 = 0 + 0.999 915 52;
  • 39) 0.999 915 52 × 2 = 1 + 0.999 831 04;
  • 40) 0.999 831 04 × 2 = 1 + 0.999 662 08;
  • 41) 0.999 662 08 × 2 = 1 + 0.999 324 16;
  • 42) 0.999 324 16 × 2 = 1 + 0.998 648 32;

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:


0.000 002 58(10) =


0.0000 0000 0000 0000 0010 1011 0100 1001 0000 0011 11(2)

5. Positive number before normalization:

0.000 002 58(10) =


0.0000 0000 0000 0000 0010 1011 0100 1001 0000 0011 11(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:


0.000 002 58(10) =


0.0000 0000 0000 0000 0010 1011 0100 1001 0000 0011 11(2) =


0.0000 0000 0000 0000 0010 1011 0100 1001 0000 0011 11(2) × 20 =


1.0101 1010 0100 1000 0001 111(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):
1.0101 1010 0100 1000 0001 111


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. 010 1101 0010 0100 0000 1111 =


010 1101 0010 0100 0000 1111


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) =
010 1101 0010 0100 0000 1111


Decimal number 0.000 002 58 converted to 32 bit single precision IEEE 754 binary floating point representation:

0 - 0110 1100 - 010 1101 0010 0100 0000 1111


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