Why are hex editors called binary editors?

Hex and binary are two different bases. Hex, in my understanding, is simply an easier to use and more convenient version of binary.

However, I often hear that hex editors are binary editors. If you search for "binary editor" on Google, you get hex editors.

A binary editor edits a file as a binary file.

Binary file - Wikipedia

A binary file is a computer file that is not a text file. The term "binary file" is often used as a term meaning "non-text file" [and is] usually thought of as being a sequence of bytes. ... Binary files typically contain bytes that are intended to be interpreted as something other than text characters.

A hex editor is a type of binary editor in which the data is represented in hexadecimal.

Hex editor - Wikipedia

A hex editor (or binary file editor or byte editor) is a type of computer program that allows for manipulation of the fundamental binary data that constitutes a computer file. The name 'hex' comes from 'hexadecimal': a standard representation for numbers that has 16 as its base.

Terminology is hard. Different people have all sorts of different names for things.

In this instance, it appears that the hex in "hex editor" refers to the conventional human-readable representation of each byte's value, whereas the binary in "binary editor" refers to the notion that you're indeed editing the file at the byte layer (and computers store bytes in binary), without consideration for higher-level text encoding and the like. Recall that files not readily representable in higher-level text form are called "binary files" or "binaries", for the same reason.

Neither is technically incorrect; they just come at the naming problem from different angles. On a personal note, though, I would tend to agree that "binary editor" is confusing on balance.

Binary editor display (in binary)

00000000 | 11111011 11111011 11111011 11111011 11110101 11111011 11111011 11111011
00001000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
00010000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
00011000 | 11110101 11111011 11111011 11111011 11111011 11111011 11111011 11111011
00100000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
00101000 | 11111011 11111011 11101111 11111011 11111011 11111011 11111011 11111011
00110000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
00111000 | 11111011 11111011 11111011 11101111 11111011 11111011 11111011 11111011
01000000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
01001000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011
01010000 | 11101111 11111011 11111011 11111011 11111011 11111011 11111011 11111011
01011000 | 11101111 11111011 11111011 11111011 11111011 11111011 11111011 11111011
01100000 | 11111011 11111011 11111011 11111011 11111011 11101111 11111011 11111011
01101000 | 11111011 11111011 11111011 11111011 11111011 11111011 11111011 11111011

Binary editor display (in hexadecimal)

00 | fb fb fb fb f5 fb fb fb fb fb fb fb fb fb fb fb
10 | fb fb fb fb fb fb fb fb f5 fb fb fb fb fb fb fb 
20 | fb fb fb fb fb fb fb fb fb fb ef fb fb fb fb fb 
30 | fb fb fb fb fb fb fb fb fb fb fb ef fb fb fb fb 
40 | fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 
50 | ef fb fb fb fb fb fb fb ef fb fb fb fb fb fb fb 
60 | fb fb fb fb fb ef fb fb fb fb fb fb fb fb fb fb

It is true that a binary editor should let you handle bytes in binary, but as you can see the base 2 is too small to give compact numerals.

Binary as raw, not base two

Generally speaking, then "binary" in binary editor doesn't refer to the base two, it actually is the antonym of "text editor".
The difference being that text editors are designed to show text, so non printing characters, new lines, control chars, invalid utf-8 code units and so on are not required to be handled safely.
The mere act of opening a file and immediately saving it can change it (due to the editor internal conversions, failures).

Binary editors on the other way, don't try to give the data any semantic and let the user safely handle it as a stream of bytes/bits/words.

Hexadecimal editors

The perfect binary editor would known every possible binary format and let you edit it, but since everyone can make its own binary format and since they change very often, it is futile to try to support all formats.
The best thing an editor could do is showing the bytes themselves, and due to the, already discussed, properties of base 16, hexadecimal numerals are very handy!

Also an experienced user can mentally translate bin to hex as they read it.
Setting/getting a bit out of a byte written in hex takes really absolutely no more effort than a byte written in bin.
To be honest I found hex easier than binary to read.

Why are hex editors called binary editors?

Summary:

A Hex Editor is used to directly edit a binary file by displaying the binary content in hexadecimal format and allowing these hexadecimal numbers to be changed.

Notes:

• Hex Editors allows editing of the raw data contents of a file, instead of other programs which attempt to interpret the data.

• Hex Editors as also called Binary Editors or Byte Editors.

• Calling them Binary Editors or Byte Editors is not really correct as the editors are changing hexadecimal numbers and not binary numbers or bytes (of course the underlying binary numbers and bytes will change if the file is saved)

Why do we edit binary use hexadecimal?

It is easier to directly view or edit/modify binary files by displaying the data in hexadecimal form and changing the hexadecimal values.

• One convenient way of representing binary numbers is using hexadecimal.

• Historically computers were programmed in assembly language, where code was written using processor instructions and meta-statements (known variously as directives, pseudo-instructions and pseudo-ops), comments and data.

  • The code is translated into binary using an assembler. The binary code can then be loaded into a process and executed.

  • Without the source code it is easier to modify the program directly using an editor that displays the program in hexadecimal rather than binary.

• Binary code is more easily readable by humans when converted into hexadecimal.

  For example, which pair of number is easier to memorise or read out to someone else?

  10110000 01100001
  

  Or

  B0 61
  

• Each hexadecimal digit represents four binary digits (bits). One hexadecimal digit represents a nibble, which is half of an octet or byte (8 bits).

  For example, byte values can range from 0 to 255 (decimal), but may be more conveniently represented as two hexadecimal digits in the range 00 to FF.

• Hexadecimal is also commonly used to represent computer memory addresses.