Extended precision

Extended precision refers to floating-point number formats that provide greater precision than the basic floating-point formats.^[1] Extended precision formats support a basic format by minimizing roundoff and overflow errors in intermediate values of expressions on the base format. In contrast to extended precision, arbitrary-precision arithmetic refers to implementations of much larger numeric types (with a storage count that usually is not a power of two) using special software (or, rarely, hardware).

^ IEEE 754 (2008, ¶ 2.1.21) defines extended precision format as "A format that extends a supported basic format by providing wider precision and range."

[1] IEEE 754 (2008, ¶ 2.1.21) defines extended precision format as "A format that extends a supported basic format by providing wider precision and range."

[1]

Computer architecture bit widths
Bit
1 4 8 12 16 18 24 26 28 30 31 32 36 45 48 60 64 128 256 512 bit slicing
Application
8 16 32 64
Binary floating-point precision
16 (×½) 24 32 (×1) 40 64 (×2) 80 128 (×4) 256 (×8)
Decimal floating-point precision
32 64 128
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