Euler constant (ℇ) is the Unicode character at U+2107 in Letterlike Symbols. Official name: EULER CONSTANT. It is a letterlike math glyph — not the Latin letter e, and not Greek gamma used for the Euler–Mascheroni constant.
Remember
Character ℇ
Unicode U+2107
Hex entity ℇ
Decimal ℇ
CSS escape \2107
Named entity (none)
Not the same e (letter) · γ (gamma) · ℮ (estimated)
Prefer ℇ or ℇ in HTML (no named form). You can also type ℇ in a UTF-8 document.
Reference
Quick Reference
One table for every form you will actually use.
Form
Code
Where it goes
Named entity
None
—
Hex entity
ℇ
HTML markup (preferred)
Decimal entity
ℇ
HTML markup
Direct character
ℇ
HTML text (UTF-8)
CSS escape
\2107
Stylesheet content
When to Use Which
Situation
Use
Letterlike Euler constant glyph
ℇ or type ℇ
Euler’s number (base of natural log)
Type e (or a math italic e if your font provides one)
Built with Hex: ℇ
Built with Decimal: ℇ
Built with CSS: ℇ
Typed: ℇ
Compare: ℇ vs e vs γ
How It Works
1. Hex:ℇ inserts code point U+2107 → ℇ.
2. Decimal: same code point as 8455 → ℇ. Same visual as hex.
3. CSS: use \2107 in content (not an HTML entity). #point::after appends ℇ.
4. Typed: paste ℇ in a UTF-8 document, or compare with e and γ.
Pitfalls & Tips
Common mistakes when working with Euler constant.
Name
No named entity
There is no HTML5 named entity for U+2107. Use ℇ or ℇ. Do not invent &euler;.
e
Not Euler’s number
The base of the natural logarithm is usually written as the letter e. U+2107 is a separate letterlike symbol.
γ
Not Euler–Mascheroni γ
The Euler–Mascheroni constant is normally written with Greek gamma (γ, γ) — not U+2107.
CSS vs HTML
Do not mix escapes
\2107 belongs in CSS strings. ℇ / ℇ belong in HTML.
Fonts
Letterlike coverage
Some fonts omit Letterlike Symbols. Prefer a font with solid math/symbol coverage when ℇ must be visible.
a11y
Add accessible text
Screen readers may not announce ℇ clearly. Prefer nearby prose (for example “Euler constant symbol”) when the glyph carries meaning.
Semicolon
End references
Always finish entities with ; — write ℇ, not ℇ.
Compatibility
Browser Support
Euler constant (U+2107) and its entity forms (ℇ, ℇ, CSS \\2107) are supported in all mainstream browsers. Visible glyphs depend on Letterlike Symbols font coverage.
✓ Universal support
Euler Constant (ℇ)
Encode with hex, decimal, CSS escape, or type the character — same code point 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+2107Full support
Bottom line: Prefer ℇ in HTML (no named form). Use ℇ when decimal form is required, and \\2107 only inside CSS content.
Remember
Key Takeaways
Unicode: Euler constant is U+2107 (decimal 8455) — glyph ℇ.
HTML: no named entity — use ℇ / ℇ / type ℇ.
CSS: use \2107 inside content for generated text.
Meaning: ℇ ≠ letter e ≠ gamma γ.
One line:U+2107 → ℇ / ℇ / CSS \2107 (no named form).
Frequently Asked Questions
Use ℇ (hex), ℇ (decimal), type ℇ directly in UTF-8, or the CSS escape \2107 in content. There is no named HTML entity for U+2107.
U+2107 (EULER CONSTANT). Hex 2107, decimal 8455. It belongs to the Letterlike Symbols block (U+2100–U+214F).
No. HTML5 does not define a named entity for U+2107. Prefer ℇ or ℇ.
Use it when you need the letterlike Euler constant glyph ℇ. Prefer the letter e for Euler’s number, and γ (γ) when you mean the Euler–Mascheroni constant.
HTML numeric entities (ℇ or ℇ) go in markup. The CSS escape \2107 goes in stylesheet strings (usually content on ::before/::after).
No. U+2107 is ℇ (Euler constant symbol). The letter e is U+0065. Greek gamma γ is U+03B3 (γ).
🤔
Did you know?
Euler constant is Unicode U+2107 (decimal 8455) — glyph ℇ (EULER CONSTANT) in Letterlike Symbols. There is no HTML5 named entity; use ℇ or ℇ. It is a letterlike math symbol — not the same as the Latin letter e, and not Greek gamma (γ, γ) used for the Euler–Mascheroni constant.
