The exponent is "Excess 128"; that is, the binary value of these 8 bits must be subtracted by 128 (decimal) to obtain the actual exponent.

For the 32 bits or 8 bytes shown below, the lowest addressed byte is bits 0-7; the next, bits 8-15; and so on.

** F_floating point** numbers have the range of approximately
plus or minus 2.9E-39 to plus or minus 1.7E+38, with a precision of approximately
seven decimal digits.

VAX-11 Floating Point Representations:
"F_Floating" Structure (32 bit "longword"): |
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31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |

Fraction (second part): bit 16 is the least significant | Sign Bit | Exponent | Fraction (first part): bit 6 is the most significant |

** D_floating point** numbers have the range of approximately
plus or minus 2.9E-39 to plus or minus 1.7E+38, with a precision of approximately
16 decimal digits.

VAX-11 Floating Point Representations:
"D_Floating" Structure (64 bit "longword"; first 32 bits): |
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31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |

Fraction: second part | Sign Bit |
Exponent | Fraction (first part): bit 6 is the most significant | ||||||||||||||||||||||||||||

second 32 bits: |
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63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |

Fraction: fourth part: bit 48 is the least significant | Fraction: third part |

** G_floating point** numbers have the range of approximately
plus or minus 5.6E-309 to plus or minus 0.9E+308, with a precision of approximately
15 decimal digits. The exponent has a bias of 1024 (not 128).

VAX-11 Floating Point Representations:
"G_Floating" Structure (64 bit "longword"; first 32 bits): |
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31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |

Fraction: second part | Sign Bit |
Exponent | Fraction (first part): bit 4 is the most significant | ||||||||||||||||||||||||||||

second 32 bits: |
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63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |

Fraction: fourth part: bit 48 is the least significant | Fraction: third part |

** H_floating point** numbers have the range of approximately
plus or minus 8.4E-4933 to plus or minus 5.9E+4931, with a precision of approximately
33 decimal digits. The exponent has a bias of 16384 (not 1024).

VAX-11 Floating Point Representations:
"H_Floating" Structure (64 bit "longword"; first 32 bits): |
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31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |

Fraction: first part | Sign Bit |
Exponent | ||||||||||||||||||||||||||||||

second 32 bits: |
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63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 | |

Fraction: third part | Fraction: second part | |||||||||||||||||||||||||||||||

third 32 bits: |
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95 | 94 | 93 | 92 | 91 | 90 | 89 | 88 | 87 | 86 | 85 | 84 | 83 | 82 | 81 | 80 | 79 | 78 | 77 | 76 | 75 | 74 | 73 | 72 | 71 | 70 | 69 | 68 | 67 | 66 | 65 | 64 | |

Fraction: fifth part | Fraction: fourth part | |||||||||||||||||||||||||||||||

fourth 32 bits: |
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127 | 126 | 125 | 124 | 123 | 122 | 121 | 120 | 119 | 118 | 117 | 116 | 115 | 114 | 113 | 112 | 111 | 110 | 109 | 108 | 107 | 106 | 105 | 104 | 103 | 102 | 101 | 100 | 99 | 98 | 97 | 96 | |

Fraction: seventh part; bit 112 is the least significant. | Fraction: sixth part |