1.361 129 467 683 753 853 853 492 4 Converted to 32 Bit Single Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 1.361 129 467 683 753 853 853 492 4(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
1.361 129 467 683 753 853 853 492 4(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: 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: 0.361 129 467 683 753 853 853 492 4.

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) 0.361 129 467 683 753 853 853 492 4 × 2 = 0 + 0.722 258 935 367 507 707 706 984 8;
  • 2) 0.722 258 935 367 507 707 706 984 8 × 2 = 1 + 0.444 517 870 735 015 415 413 969 6;
  • 3) 0.444 517 870 735 015 415 413 969 6 × 2 = 0 + 0.889 035 741 470 030 830 827 939 2;
  • 4) 0.889 035 741 470 030 830 827 939 2 × 2 = 1 + 0.778 071 482 940 061 661 655 878 4;
  • 5) 0.778 071 482 940 061 661 655 878 4 × 2 = 1 + 0.556 142 965 880 123 323 311 756 8;
  • 6) 0.556 142 965 880 123 323 311 756 8 × 2 = 1 + 0.112 285 931 760 246 646 623 513 6;
  • 7) 0.112 285 931 760 246 646 623 513 6 × 2 = 0 + 0.224 571 863 520 493 293 247 027 2;
  • 8) 0.224 571 863 520 493 293 247 027 2 × 2 = 0 + 0.449 143 727 040 986 586 494 054 4;
  • 9) 0.449 143 727 040 986 586 494 054 4 × 2 = 0 + 0.898 287 454 081 973 172 988 108 8;
  • 10) 0.898 287 454 081 973 172 988 108 8 × 2 = 1 + 0.796 574 908 163 946 345 976 217 6;
  • 11) 0.796 574 908 163 946 345 976 217 6 × 2 = 1 + 0.593 149 816 327 892 691 952 435 2;
  • 12) 0.593 149 816 327 892 691 952 435 2 × 2 = 1 + 0.186 299 632 655 785 383 904 870 4;
  • 13) 0.186 299 632 655 785 383 904 870 4 × 2 = 0 + 0.372 599 265 311 570 767 809 740 8;
  • 14) 0.372 599 265 311 570 767 809 740 8 × 2 = 0 + 0.745 198 530 623 141 535 619 481 6;
  • 15) 0.745 198 530 623 141 535 619 481 6 × 2 = 1 + 0.490 397 061 246 283 071 238 963 2;
  • 16) 0.490 397 061 246 283 071 238 963 2 × 2 = 0 + 0.980 794 122 492 566 142 477 926 4;
  • 17) 0.980 794 122 492 566 142 477 926 4 × 2 = 1 + 0.961 588 244 985 132 284 955 852 8;
  • 18) 0.961 588 244 985 132 284 955 852 8 × 2 = 1 + 0.923 176 489 970 264 569 911 705 6;
  • 19) 0.923 176 489 970 264 569 911 705 6 × 2 = 1 + 0.846 352 979 940 529 139 823 411 2;
  • 20) 0.846 352 979 940 529 139 823 411 2 × 2 = 1 + 0.692 705 959 881 058 279 646 822 4;
  • 21) 0.692 705 959 881 058 279 646 822 4 × 2 = 1 + 0.385 411 919 762 116 559 293 644 8;
  • 22) 0.385 411 919 762 116 559 293 644 8 × 2 = 0 + 0.770 823 839 524 233 118 587 289 6;
  • 23) 0.770 823 839 524 233 118 587 289 6 × 2 = 1 + 0.541 647 679 048 466 237 174 579 2;
  • 24) 0.541 647 679 048 466 237 174 579 2 × 2 = 1 + 0.083 295 358 096 932 474 349 158 4;

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:


0.361 129 467 683 753 853 853 492 4(10) =


0.0101 1100 0111 0010 1111 1011(2)

5. Positive number before normalization:

1.361 129 467 683 753 853 853 492 4(10) =


1.0101 1100 0111 0010 1111 1011(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:


1.361 129 467 683 753 853 853 492 4(10) =


1.0101 1100 0111 0010 1111 1011(2) =


1.0101 1100 0111 0010 1111 1011(2) × 20


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): 0


Mantissa (not normalized):
1.0101 1100 0111 0010 1111 1011


8. Adjust the exponent.

Use the 8 bit excess/bias notation:


Exponent (adjusted) =


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


0 + 2(8-1) - 1 =


(0 + 127)(10) =


127(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;
  • 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) =


127(10) =


0111 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 23 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. 010 1110 0011 1001 0111 1101 1 =


010 1110 0011 1001 0111 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) =
0111 1111


Mantissa (23 bits) =
010 1110 0011 1001 0111 1101


Decimal number 1.361 129 467 683 753 853 853 492 4 converted to 32 bit single precision IEEE 754 binary floating point representation:

0 - 0111 1111 - 010 1110 0011 1001 0111 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