July 1993/Varying Floating-Point Precision/Table 1

Table 1 Comparison of floating-point sizes and precisions (on a PC)

Type         Size (bytes)  Significant  Epsilon
                           Digits
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float        4             7            1.192092896e-07
double       8             15           2.2204460492503131e-016
long double  10            19           5.4210108624275221706e-020