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Calculate SHA256 from the hash, extract 2 rightmost bytes from the result, interpret them as a big-endian unsigned integer and take the last 4 digits in decimal form for display. SHA256 is always used here.
Please mind that hash is a real hash byte value, not the Base64 form or the hexadecimal representationthe hash string should be in Base64 format.
In this example we have generated a hash string and calculated a verification code.
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