This is the thing bugging me. I'd like to see some of my files in binary or plaintext format, but I can't figure out how to do it for all files. I can open some image files in plaintext using Textedit, but that's all I can figure out. Anyone know anything?
od -h filename | less" in your Terminal.app.
I like that I don't have to learn emacs or download a new app with this answer -- in my opinion its the most succinct and best time-saver. Sep 22, 2019 at 19:40
To read binary/text file:
I'd recommend BBEdit (used to be TextWrangler) as a good general purpose plain-text editor. If you have this in the Dock, you can drag any file on to it and the file will be opened as plain text.
You can use Emacs hexl-mode.
In the terminal, type 'emacs' and the name of the file you want to open. When emacs opens up the file, type option-x hexl-mode.
I use HexEdit for this sort of thing. It can open any file and give you its hex and plaintext representation.
The editor of my choice for these kinds of things is Smultron.
You can always drop into a Terminal shell session, and use
hexdump to view any file as a text or hexadecimal file.
TextEdit will also display plain text files (as will about any other text editor, as noted by others).
Open the file with TextEdit - the plain text editor on MacOS - I was surprised it worked after trying for many days, many ways from many sources