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Aug 08, 2026
HTML Entity Detail
HTML Entity - Capital Letter Xi
Capital Letter Xi is a uppercase Greek alphabet letters used in mathematics, science, and engineering. This HTML entity enables web developers to display this character reliably across all browsers without encoding issues.
Symbol preview
Ξ
Unicode
U+039E;
HTML entity
Ξ
CSS code
\039E
Usage Examples
Use this HTML entity in mathematical and scientific notation. For example, Σ for summation, Π for product, Δ for difference.
Common Mistakes
⚠️
Mistake: Using Latin capital letters instead of Greek letters in formulas
Fix: Greek letters have specific mathematical meanings. Use Σ not S for summation, Π not P for product, Δ not D for change. The meaning changes if you use the wrong alphabet.
⚠️
Mistake: Confusing uppercase Greek letters that look like Latin letters
Fix: Capital alpha (Α) looks like A, capital beta (Β) looks like B, etc. Use Latin letters for Latin text and Greek letters for Greek/math context — they may be different Unicode characters.
Capital Letter Xi
Select any code to highlight it before copying.
Category: Greek Alphabet - Capital Letters
| Unicode | U+039E; |
|---|---|
| Hex Code | Ξ |
| HTML Code | Ξ |
| HTML Entity | Ξ |
| CSS Code | \039E |
| Windows Shortcut | |
| Mac Shortcut | |
HTML code example
CSS code example
Last updated: 17 Aug 2026
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