How to Type an Infinity Symbol
The infinity symbol (∞), also called the lemniscate, represents an unbounded quantity in mathematics, endless possibilities in philosophy, and unlimited concepts in design.
Quick Reference
Windows
Hold Alt and type 236 on the numeric keypad.
Alt + 236
Mac
Press Option + 5.
Option + 5
Linux
Press Ctrl + Shift + U, type 221E, press Enter.
Ctrl + Shift + U, 221E, Enter
HTML
Use the HTML entity ∞ or numeric ∞.
∞ or ∞
Common Uses
The infinity symbol has applications across mathematics, philosophy, technology, and creative design. It represents concepts that have no bound or limit.
- Mathematics: Limits, calculus (lim x→∞), infinite series
- Set theory: Infinite sets, cardinality of infinite collections
- Programming: Infinite loops, unbounded data structures
- Technology: Unlimited storage, infinite scroll
- Design: Logo design, jewelry, tattoos representing eternal concepts
- Philosophy: Endless time, eternal recurrence, boundless space
Mathematical Context
In mathematics, the infinity symbol represents different concepts depending on context:
- Limits: As x approaches infinity (x → ∞)
- Unbounded intervals: [0, ∞) means all non-negative numbers
- Infinite sums: ∑(n=1 to ∞) represents an infinite series
- Division by zero: Sometimes notated as 1/0 → ∞ (with caveats)
Note that infinity is not a number but rather a concept representing unboundedness.
History and Etymology
The infinity symbol (∞) was introduced by mathematician John Wallis in 1655. The term "lemniscate" comes from the Latin word "lemniscus," meaning ribbon, describing the symbol's curved, ribbon-like shape.
The symbol may have been inspired by the Roman numeral for 1000 (CIƆ) or simply chosen for its elegant representation of endlessness through a continuous loop.
Technical Details
Unicode: U+221E
HTML Entity: ∞
HTML Decimal: ∞
Alt Code (Windows): Alt + 236
Name: INFINITY