(Ø) O with Slash / O with Line Through It : Shortcuts

Have you ever seen an “O with slash through it” (Ø or ø) and thought, “Wait, what is that? Is it a zero? Is it a special symbol? Or just a fancy letter?”

You’re not alone. This letter O with line through it confuses many people because it looks like both the letter O and the number 0 (zero). But the truth is: the O with line through it symbol is a real letter with a unique history, sound, and meaning.

This comprehensive guide breaks down exactly what the symbol means, how it differs from lookalikes, and how to type it on any device.

What is the “O with a Slash” (Ø)?

The letter O with line through it, written as Ø (uppercase) or ø (lowercase), is a real letter — not just a stylized “O”.

• In the Norwegian O with slash and Danish O with slash, it’s considered a separate vowel in the alphabet.
• Think of it like Spanish “ñ” or German “ü” — it’s still a letter, but with its own sound.
• Fun fact: in the alphabet, Ø comes after Z.

So if you’ve ever wondered, “What is an O with a slash through it?” — it’s not a design choice. It’s an actual letter.

O with a line through it meaning (Ø)

So what does O with slash or O with a line through it mean?

• In Norwegian and Danish: Ø is pronounced kind of like the “i” in “bird” or the “u” in “burn.” It’s not exactly the same, but close enough if you’re just learning.
• In phonetics (IPA): It represents a rounded front vowel. That’s a fancy linguistic way of saying it’s a unique sound you don’t usually hear in English.
• In math and science: Sometimes people mistake Ø for other symbols (like diameter ⌀ or empty set ∅), but those are different symbols entirely.

So the bottom line: Ø = a real letter with its own sound, not just a stylistic choice.

How to Type O with a Slash (Ø) on Any Device

Typing the O with slash alt code is easier than you think.

On Windows (Alt Codes):

• For capital O with line through it (Ø), hold down the Alt key and type 0216 → Ø.
• For o with line through it lowercase (ø) or small o with line through it, use Alt + 0248 → ø.

On Mac:

• Press Option + O for the lowercase ø
• Press Option + Shift + O for the uppercase Ø.

On Linux:

• Linux users can rely on the Compose key. Just press Compose, then type / followed by o, and it will give you ø.

On iPhone/Android:

• Hold down the letter O on the keyboard, and a menu pops up.
• Slide to choose ø.

Unicode Codes:

• Ø (uppercase): U+00D8
• ø (lowercase): U+00F8

Zero with a Slash vs O with a Slash

Many people ask, “Is O with a slash a zero?” The answer: No.

This is where people get tripped up. Ø is not the same thing as “0 with a slash”.

• Ø (letter O with slash) → Used in languages like Norwegian and Danish.
• 0̸ (zero with slash) → Just a way to make sure you don’t confuse the number zero with the letter O.
• ∅ (empty set symbol) → A mathematical symbol used in set theory to represent a null or empty set.
• ⌀ (diameter symbol): A technical symbol used in engineering and architectural drawings to indicate the diameter of a circular object.

Quick Comparison: Ø vs Ö vs ∅ vs ⌀

Quick FAQ

Final Thoughts

The O with a slash (Ø) isn’t just some random design — it’s a letter with real history, meaning, and pronunciation. Whether you’re learning Norwegian, trying to type it in a name, or just stumbled across it online, now you know:

• It’s not a zero.
• It’s not just a circle with a line.
• It’s a letter O with slash that carries meaning, pronunciation, and cultural value.

For more detailed information about Ø, you can visit its Wikipedia page

• Learn about N with Tilde (Ñ / ñ)
• Type ü (U with Two Dots)
• Learn about O with Accent Mark
• Learn about Thorn Letter