Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Convert a hexadecimal string to a real number
ResourceFunction["HexStringToReal"][s] gives the machine double number corresponding to the hexadecimal string s, using 11 bits for the exponent. 

ResourceFunction["HexStringToReal"][s,{e,prec}] computes the real number in precision prec, taking e bits for the exponent field. 
Find the number for a hex‐encoded machine float:
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Translate hex‐encoded string to a software float:
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Check that it is not a machine number:
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The input form will also show that it has an associated precision:
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Requesting more precision than is present in the hexadecimal representation will lead to padding with zero bits, which will appear as arbitrary digits in decimal form:
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Wolfram Language 11.3 (March 2018) or above
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