Bidirectional arrow block (↹) is Unicode U+21B9 in the Arrows block. It is the Tab-key style glyph: leftwards arrow to bar over rightwards arrow to bar. HTML has no standard named entity — use numeric or CSS forms (or type the character in UTF-8).
Remember
Character ↹
Unicode U+21B9
Hex entity ↹
Decimal ↹
Named entity (none)
CSS escape \21B9
Not the same Tab control U+0009
All of these produce the same glyph: ↹. Prefer typing ↹ in UTF-8 when you can; use ↹ / ↹ or CSS for generated content.
Bidirectional arrow block using Hex Code: ↹
Bidirectional arrow block using HTML Code: ↹
Bidirectional arrow block using CSS Entity: ↹
Typed directly: ↹
How It Works
1. Hex:U+21B9 → ↹ in HTML. The browser turns it into ↹.
2. Decimal: same code point as 8633 → ↹. Same result as hex.
3. CSS: use \21B9 in content (not an HTML entity). #point::after appends that ↹ after the paragraph text.
4. Typed ↹: fine in UTF-8 source. All four lines show the same glyph.
Pitfalls & Tips
Common mistakes when working with bidirectional arrow block (↹).
Named
No &name; form
U+21B9 has no standard named entity — use ↹ or ↹.
Tab
Not ASCII tab
↹ is a visible symbol. ASCII tab (U+0009) is a control character for indentation.
a11y
Say “Tab”
Screen readers may not announce the glyph. Pair it with the word Tab or use tut-sr-only.
Fonts
Check Arrows coverage
Some UI fonts omit U+21B9. Prefer fonts with solid Arrows block support.
CSS vs HTML
Do not mix escapes
\21B9 belongs in CSS. ↹ / ↹ belong in HTML.
Semicolon
End references
Always finish with ; — write ↹, not ↹.
Compatibility
Browser Support
Bidirectional arrow block (U+21B9) and its entity forms (↹, ↹, CSS \\21B9) are supported in all mainstream browsers. Glyph quality depends on font support for the Arrows block.
✓ Universal support
Bidirectional Arrow Block (↹)
Type ↹, or encode with hex, decimal, or CSS escape — same glyph everywhere encoding is supported.
100%Browser coverage
Google ChromeSupported
Yes
Microsoft EdgeSupported
Yes
Mozilla FirefoxSupported
Yes
Apple SafariSupported
Yes
OperaSupported
Yes
Internet ExplorerAll versions
Yes
U+21B9 / entitiesFull support
Bottom line: Prefer a typed ↹ or ↹ for keyboard labels. Use decimal when generating markup, and \\21B9 only inside CSS content.
Remember
Key Takeaways
Unicode: bidirectional arrow block is U+21B9 (decimal 8633).
HTML: use ↹ or ↹ (no named entity).
CSS: use \21B9 inside content for generated icons.
Watch out: ↹ ≠ ASCII tab (U+0009).
One line:U+21B9 → ↹ / ↹ / CSS \21B9.
Frequently Asked Questions
Use ↹ (hex), ↹ (decimal), or the CSS escape \21B9 in the content property. All render ↹. You can also paste ↹ directly if your file is UTF-8. There is no standard named entity.
U+21B9 (hex 21B9, decimal 8633). Unicode names it LEFTWARDS ARROW TO BAR OVER RIGHTWARDS ARROW TO BAR. It belongs to the Arrows block.
No. HTML5 / WHATWG does not define a named character reference for U+21B9. Prefer ↹, ↹, or a typed ↹ in UTF-8.
No. ↹ is a visible symbol often printed on Tab keys. ASCII tab is U+0009 — a control character that inserts a tab, not a glyph you display for decoration.
HTML entities (↹ or ↹) go in markup. The CSS escape \21B9 is used in stylesheets (usually in the content property of ::before/::after). Both render ↹.
In keyboard UI labels, shortcut docs, and tutorials that show a Tab-style glyph. Label it “Tab” for accessibility when meaning matters.
🤔
Did you know?
Bidirectional arrow block is Unicode U+21B9 (decimal 8633) in the Arrows block — official name LEFTWARDS ARROW TO BAR OVER RIGHTWARDS ARROW TO BAR. There is no standard named HTML entity. It is often drawn on Tab keys. It is not the ASCII tab character (U+0009).
