About Superscript Plus Sign
Superscript Plus Sign is the Unicode character ⁺ at codepoint U+207A in the Superscripts and Subscripts block of the Basic Multilingual Plane (BMP).
Reference
The raised plus of ion charges and one-sided limits. Unicode files it as Sm, a mathematical symbol, with bidirectional class ES, European Separator — the class for a sign attached to a number — and it carries the derived Math property. That makes it the only mathematical character among the punctuation marks it sits beside. Its compatibility decomposition is <super> 002B, which is the standard saying it exists to round-trip older encodings rather than to be typed fresh, and NFKC and NFKD duly replace it with an ordinary plus. There is no HTML named entity and no Windows-1252 slot.
Typical uses
- Ion charges in plain text: Na⁺, Ca²⁺
- One-sided limits and positive parts in mathematical notation
- Anywhere an exponent or charge is needed and no styling is available
At a glance
- U+207A, Superscripts and Subscripts; Unicode 1.1 (1993); general category Sm
- Bidirectional class ES; East Asian Width Neutral; line break class AL
- Derived Math property; no HTML named entity; no Windows-1252 slot
- NFKC and NFKD replace it with U+002B
Historical Notes
Origins
Like the rest of its block it has no independent typographic history: it was encoded to complete a set of raised characters that older encodings already carried, and the standard's own decomposition records that intent.
Unicode
Unicode 1.1, released in 1993, in Superscripts and Subscripts. The block holds raised digits, the raised plus, minus, equals and parentheses — a small notational kit rather than a general superscript facility, which is why the recommended route to raised text has always been markup.
The one mathematical character in the neighbourhood
Unicode's general category for this character is Sm and it carries the derived Math property, which none of the punctuation marks around it does apart from the prime. Its bidirectional class is ES, the class reserved for a sign that attaches to a number and is laid out with it. Both are the standard's own statement that this is notation, not decoration.
Developer Notes
| Unicode Codepoint | |
| Decimal | |
| UTF-8 (hex) | |
| UTF-16 (hex) | |
| HEX Entity | |
| HTML Entity | |
| CSS (\xxxx) | |
| JavaScript | |
| Python |
How to Use Superscript Plus Sign
To use the Superscript Plus Sign symbol (⁺) in HTML, insert the
entity ⁺ directly into your markup. The decimal entity ⁺ works in any HTML-serialised document.
In CSS pseudo-elements use content: '\207A';.
In JavaScript and TypeScript the escape '\u207A' evaluates to ⁺. In Python source, write '\u207A'.
The character encodes to E2 81 BA as UTF-8 bytes and 207A as UTF-16 code units. Its decimal codepoint is 8314.
This is a text-based Unicode character. It will render in the current font on most platforms. If a font lacks this glyph, the browser may show a placeholder or fall back to a system font.
Things to know
- NFKC and NFKD replace it with an ordinary plus sign. A normalised Na⁺ becomes Na+.
- No named HTML entity. Write ⁺ or ⁺.
- Bidirectional class ES, so it lays out as part of a number rather than as a neutral symbol.
- Font coverage is the practical risk: faces that ship the superscript digits frequently skip the operators, so this character falls back more readily than ⁰ to ⁹ do. Test rather than assume.
- Where you control the styling, raise a normal plus sign with the font's superscript feature instead.
In the Wild
On 5 August 2026 English Wikipedia's article about its own block carried this character once, as a chart specimen.
The pages where it would be expected carried none. English Wikipedia's article on ions runs to 35,529 characters and contains no raised plus; the article on sodium, 65,266 characters, contains none either. Both loaded fully. Their charges are set with markup, which produces the same appearance and leaves no character behind.
That is the honest position for this character. It is a plain-text fallback, and published web pages are not plain text. Where it does earn its place — a filename, a spreadsheet cell, a message with no formatting — there is nothing else that will do the job. Pages change; this is what those showed on the day.
FAQ
Should I use it for ion charges?
In plain text, yes. Anywhere with styling, raise an ordinary plus with markup — the weight will match the surrounding font.
Does it survive normalisation?
Not under NFKC or NFKD, which replace it with U+002B. NFC and NFD leave it alone.
Is there an HTML entity?
No named one. Use ⁺ or ⁺.
Why does it sometimes render as a box?
Because font coverage for the superscript operators is thinner than for the superscript digits. A face can ship ⁰ to ⁹ and skip this one.