Control characters
C1 CONTROL CHARACTERS (U+0080–U+009F)
A second block of 32 control codes inherited from ISO 8859. In Unicode they are controls; in Windows-1252 the same byte values are curly quotes, the em dash and the euro sign.
- Range
U+0080–U+009F- Category
- Control characters
- Removed by default
- No
- Governing option
- Control characters
--controls - Can be load-bearing
- No
Where it comes from
Almost always from decoding a Windows-1252 file as if it were Latin-1 or UTF-8. That is why C1 controls and mojibake travel together.
Why it matters
Their presence is a reliable signal that an encoding step went wrong somewhere upstream, and the text may be damaged in ways a cleaner cannot repair.
Before and after
U+0093 and U+0094 are where Windows-1252 keeps its curly quotes. Decoded as Unicode they are controls.
The character is shown as a labelled chip so you can see where it sits. In your text it draws nothing at all.
When it is legitimate
Essentially never in modern text. Any occurrence is worth tracing back to the encoding step that produced it.
How to remove it
Turn on Control characters (`--controls`). U+0085 NEXT LINE is deliberately excluded — it is a line break and belongs to `-n`.
Is it an AI watermark?
Not a watermark
No. C1 controls are an encoding accident. If you see them, look for a mis-decoded file rather than a hidden message.
No connection to machine-generated text. It comes from software, from a keyboard, or from a person.
Questions
Does their presence mean my file is broken?
Usually yes. C1 controls in text almost always mean a Windows-1252 file was read as something else. Fixing the decoding is better than deleting the characters.
Why is U+0085 not included?
Because it means "next line". Removing it would join two lines; `-n` folds it to a line feed instead.
Check your own text
Paste anything into the cleaner to see every hidden character it contains, with position, codepoint and what happens to each one. Nothing is uploaded.