About Leftwards Arrow With Hook Left Arrow With Hook
Leftwards Arrow With Hook Left Arrow With Hook is the Unicode character ↩ at codepoint U+21A9 in the Arrows block of the Basic Multilingual Plane (BMP).
Reference
A hooked arrow that Unicode files as So, a symbol rather than a mathematical operator, unlike the plain directional arrows it sits among — and it takes the whole technical profile that goes with that: East Asian Width Neutral rather than Ambiguous, and line-break class AL rather than AI, so unlike its Sm neighbours it takes one terminal cell everywhere. It still counts as maths: the character carries Other_Math in PropList and the derived Math property, and Unicode's math-class table files it as a relation. Emoji since version 0.6 but not Emoji_Presentation, so it is text unless a variation selector says otherwise. Two HTML names, both mathematical. The chart gives it no annotation at all.
Typical uses
- Return, reply and "go back" affordances in interfaces
- The soft line break, in editors that show one
- Injections in mathematics, read "hooks into", pointing left
- With a variation selector, the right-arrow-curving-left emoji
At a glance
- U+21A9, Arrows; Unicode 1.1 (1993); general category So
- East Asian Width Neutral; line break class AL; Bidi_Mirrored No
- HTML: ↩, ↩
- Emoji since E0.6, text by default; no Windows-1252 slot
Historical Notes
Origins
The hook is a mathematician's mark before it is an interface designer's: an arrow whose tail curls back is the standard notation for an injective map. The interface reading came later and from a different direction — the shape looks like the motion of a line wrapping, or a reply returning.
Unicode
Unicode 1.1, released in 1993, in the Arrows block. The chart carries no annotation, no alias and no cross-reference for this character. Its formal mathematical status is stated elsewhere in the database rather than in the chart: PropList lists it under Other_Math, which is how a character that is not general category Sm still ends up with the derived Math property.
The naming disagreement
Unicode's own emoji data file, which quotes the short names used in emoji pickers and read aloud by screen readers, gives this character as "right arrow curving left" — describing the journey. Unicode's character name describes the destination: LEFTWARDS ARROW WITH HOOK. Both names are in the same standard's files, and they are not translations of each other.
Developer Notes
| Unicode Codepoint | |
| Decimal | |
| UTF-8 (hex) | |
| UTF-16 (hex) | |
| HEX Entity | |
| HTML Entity | |
| CSS (\xxxx) | |
| JavaScript | |
| Python |
How to Use Leftwards Arrow With Hook Left Arrow With Hook
To use the Leftwards Arrow With Hook Left Arrow With Hook 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: '\21A9';.
In JavaScript and TypeScript the escape '\u21A9' evaluates to ↩. In Python source, write '\u21A9'.
The character encodes to E2 86 A9 as UTF-8 bytes and 21A9 as UTF-16 code units. Its decimal codepoint is 8617.
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
- General category So, not Sm, so any code branching on "is this a maths symbol" by category will miss it. The derived Math property is the correct test; PropList's Other_Math is where it comes from.
- Emoji but not Emoji_Presentation: bare it is monochrome text, with U+FE0F it is the coloured button. If your arrow arrives grey when you wanted blue, a missing selector is why.
- It is not the Return key character. Unicode encodes a separate one for that; this is a widely adopted stand-in, not the official symbol.
- East Asian Width Neutral and line-break class AL, unlike the Sm arrows in the same block — one cell in a terminal, in any locale.
- Pattern_Syntax applies; no Windows-1252 slot; stable under all four normalisation forms.
In the Wild
This character is close to invisible in ordinary text, and 5 August 2026 said so with unusual clarity.
Wikipedia's article about the Arrows block carries it four times as a chart specimen — the character appearing in a table of the block's contents, which is not usage. It appears once more on the article about the Enter key, and it is also about the character rather than in it: "U+21B5 ↵ DOWNWARDS ARROW WITH CORNER LEFTWARDS or U+21A9 ↩ LEFTWARDS ARROW WITH HOOK are sometimes used instead."
No page simply used it. That is consistent with what the character mostly is: an icon drawn into a button, not a character typed into a sentence. Pages change; this is what those showed on the day.
FAQ
Is this the Return key symbol?
Not officially. Unicode designates a different character for that job; this one caught on as a substitute and is now more familiar than the original.
Why does it render flat instead of as a blue button?
Because it is not Emoji_Presentation. Follow it with U+FE0F to request the coloured form.
What does it mean in mathematics?
An injection — a map that slots one set into another without collisions. The rightwards version is the one usually written.
Why do two standards name it differently?
One name describes where the arrow ends up pointing; the other narrates the whole curve. Both come out of Unicode's own files.