What's the fastest way to convert a byte array to a hex string in C++?

Question

There are a lot of different ways to convert a byte array to a hex string. What is the fastest way?

There are possibly more.

[This](http://stackoverflow.com/a/9893603/2970947) answer scored highly the last time — Elliott Frisch, Dec 13 '13 at 06:30

score 5 · Accepted Answer · answered Dec 13 '13 at 06:27

Testing over 100,000 iterations found:

the lookups solution took 63 ms.
the sprintf solution took 827 ms (~10x more than #1).
the stringstream solution took 1684 ms (~25x more than #1).

All results from my own test system.

This is probably a surprise to no one very familiar with C and C++ but given the number of different approaches available for solving this problem, having a Q&A on the approach with the best performance could be useful for people less familiar with C/C++.

Ugh, you could just edit your question. – Aniket Inge Dec 13 '13 at 06:29 — Aniket Inge, Dec 13 '13 at 06:29

What's the fastest way to convert a byte array to a hex string in C++?

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