Hex Editor for Mac or Any Platform Actually - MacVim (Vim)

Here's how to use Vim as a handy HEX editor:

1. Open the file in Vim.
2. Run the command to convert

   :% ! xxd</li>

3. Edit all you need (i to get into insert edit mode)
4. Once done, run to convert back

   :% ! xxd -r</li>

5. Save (it's :wq)
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