What ₅ means
Its role comes from the notation around it. In a chemical formula, a subscript counts atoms of the element before it; in math, it can label an indexed item, as in x₅. The notation determines what that index stands for.
For structured text, semantic subscript formatting keeps the digit as 5 and controls its position. The standalone ₅ is a compatibility character, so normalization can turn it into ordinary 5.
Don't confuse it with
1Questions people ask
1Why does ₅ show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type ₅
Windows (Word)
Alt+XType 2085, then Alt+X to get ₅.
Windows
Win+Rrun charmap for the full table, or use the emoji picker's Ω symbols tab (Win + .).
macOS
Control+Command+SpaceOpen the character viewer and search “subscript five”.
Linux
Ctrl+Shift+UType 2085, then Enter or Space.
HTML
₅CSS
\2085Codes and encoding1 code points
HTML decimal
₅
HTML hex
₅
CSS content
content: "\2085";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%E2%82%85
1
On screen
1
Code points
1
JS .length
3
UTF-8 bytes
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.