Online tool to determine number of bytes for UTF-8 characters?

Question

Is there an online tool that will tell me the number of bytes in a UTF-8 character? Or, if not, how do I determine this?

I'm currently trying to determine the number of the bytes for the left and right floor characters:

⌊ (\[LeftFloor]) = U+230A https://unicode-table.com/en/230A/

⌋ (\[RightFloor]) = U+230B https://unicode-table.com/en/230B/

I looked through this FAQ, but was unable to find an answer.

Update

Thanks for the answers! I tried the various byte counters, and I ran into two issues:

(1) I found that one program, Mego's Byte Counter, gives a different UTF-8 value from the other three for the italicized pi (see first screenshot). Either (as seems more likely) Mego's is incorrect, or the other three all are. Whichever of these is incorrect, they may have other errors as well.

Here are my test glyphs:

glyph 1: 𝜋 (italicized pi)

glyph 2: π (plain-text pi)

For glyph 1 (𝜋), Mego's Byte Counter reports six bytes, while the others say four:

For glyph 2 (π), all report two bytes:

(2) With some glyphs, like those for pi, it's pretty easy to tell when you aren't using the lowest-byte-count version of the glyph (you want the plain-text rather than the italicized version). But what if you're dealing with ones that aren't so obvious, like arrows and other more unusual symbols? Are there cases where you might, say, use an arrow and get x bytes, not realizing there's another version of an arrow that is x-1 bytes? If so, is there a good online listing of minimal-UTF-8-byte-count versions of each type of glyph?

Now you might ask: Why not just copy the glyph from the front end of the program you're using (in my case, Mathematica), since that way you'll be able to determine the byte count of the actual glyph the program uses. The problem is that, when I do that, I don't get the glyph:

Answer 1

TIO includes a byte counter. For languages with an SBCS, this just counts the number of characters, but for most languages, you'll notice they use UTF-8. For example, if you go to the Python 3 TIO, in the top-right corner, it says "UTF-8".

You can simply paste your code into the code box for any language that uses UTF-8 encoding and it'll give you the character and byte count in that encoding.

Just be careful not to use a language with an SBCS - that'll just give the character count as the byte count.

Answer 2

I've always used this byte counter which in fact gives you both character and byte counts.

Answer 3

Here a couple of counters made by CGCC community members:

• Byte Counter by Mego (account deleted)

  Outputs all (supported) code pages where the inputted text is a valid encoding. Outputs the length and the list of bytes in hex/ The current list of supported encodings are:

  supported_pages = [
   'ascii', 'cp037', 'cp1006', 'cp1026', 'cp1140', 'cp1250',
   'cp1251', 'cp1252', 'cp1253', 'cp1254', 'cp1255', 'cp1256', 'cp1257',
   'cp1258', 'cp424', 'cp437', 'cp500', 'cp720', 'cp737', 'cp775', 'cp850',
   'cp852', 'cp855', 'cp856', 'cp857', 'cp858', 'cp860', 'cp861', 'cp862',
   'cp863', 'cp864', 'cp865', 'cp866', 'cp869', 'cp874', 'cp875', 'iso8859_1',
   'iso8859_10', 'iso8859_13', 'iso8859_14', 'iso8859_15', 'iso8859_16',
   'iso8859_2', 'iso8859_3', 'iso8859_4', 'iso8859_5', 'iso8859_6', 'iso8859_7',
   'iso8859_8', 'iso8859_9', 'jelly', 'koi8_r', 'koi8_u', 'mac_cyrillic',
   'mac_greek', 'mac_iceland', 'mac_latin2', 'mac_roman', 'mac_turkish',
   'ptcp154'
  ]

  _Source

• bytes by ETHproductions

  Supports 20 different encodings, able to be chosen from a dropdown menu. Has permalinks and a bookmarklet available. Currently supports UTF-8, UTF-16, ISO-8859-1, CP437, ASCII and more

_Source