Double SHA256

A double SHA256 is used to protect against length extension attacks by ensuring that the final SHA256 output is produced from a 32 byte input.

Eg, You can enter a very large string, or hex number consisting of any number of bytes, and the first SHA256 pass will produce a 32 byte number. That resulting 32 byte number is then passed again for a second time through the SH256 hashing function thus ensuring that the final output was produced from a 32 byte input.

Example Hex String : 1BEE5A29DAF06786A5516D9226B30BBDBF422A7ED475E42C3F930EA04C612091

Double SHA256 Result

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