Greek letters · U+3A9

ΩOmega symbol

Ω is the Omega character. It is text, not a picture — it takes the colour of the type around it and pastes into anything.

How to type it
Unicode
U+3A9
Alt code
Alt+937
HTML
Ω
Unicode name
Greek Capital Letter Omega
Ω
Your font
01 — Origin

Where the Omega symbol comes from

Omega is the last letter of the Greek alphabet, which is why it means an ending — the phrase “alpha and omega” is older than any of its scientific uses. Its role as the unit of electrical resistance dates to 1867 and honours Georg Ohm.

Ohms in electronics — 220 Ω, 4.7 kΩ — angular velocity in physics, and the last or ultimate version of anything in branding. Also the standard label on a resistor colour chart.

Worth knowing
The ohm sign Ω once had its own Unicode code point separate from the Greek letter. It still exists but is deprecated: use the Greek capital omega for both.
02 — Codes

Omega symbol codes

Four notations, one result: whatever you copy here comes out as U+3A9.

03 — How to type

How to type Ω on any keyboard

Keyboard, code, markup or document — the route to U+3A9 differs by tool.

Windows
Hold Alt and type 937 on the numeric keypad, then release. Without a keypad, use the Character Map app (search “charmap”).
Mac
Press Control + Command + Space to open the character viewer, then search “omega”. Double-click to insert.
Phone
There is no shortcut on a phone keyboard. Tap the symbol at the top of this page, then long-press in any text field and choose Paste.
Web and code
In HTML write Ω or Ω. In CSS content: "\03A9". Make sure the page is served as UTF-8 and the raw character works too.
04 — Font support

Will Ω actually show up?

We checked 147 fonts installed on a normal machine and counted how many of them contain this character. A symbol missing from a font is drawn as an empty box — the text is still correct, it just cannot be drawn.

86% 127 of 147 fonts

Safe in most places. Common fonts have it. Older or decorative fonts sometimes do not, so a fallback font will kick in.

05 — Similar

Symbols people confuse with Ω

These look alike but are different characters — different codes, different fonts, sometimes different meaning.

06 — Related

Other Greek letters used as symbols

The rest of the family, one page each — origin, typing routes and font support, across all 5.

α Alpha symbolIn 86% of system fonts β Beta symbolIn 86% of system fonts Δ Delta symbolIn 86% of system fonts λ Lambda symbolIn 86% of system fonts Σ Sigma symbolIn 86% of system fonts
07 — Same block

Greek letters

Alpha to omega, the alphabet science borrowed.

All greek letters →
08 — FAQ

Omega symbol — questions

How do I type the Omega symbol?
On Windows hold Alt and type 937 on the numeric keypad. On Mac open the character viewer with Control + Command + Space and search “Omega”. Or just tap the symbol on this page — it goes straight to your clipboard.
What is the HTML code for Ω?
Write it as Ω or Ω in HTML, \03A9 in CSS content, and \u03A9 in JavaScript. All four produce the same character.
Is Ω an emoji?
No. Ω is a text character — it takes the colour of the text around it and works in usernames, filenames and documents. An emoji is replaced by a colour picture and is sometimes stripped by forms and systems.
Why does Ω show as a box on some devices?
Because that font has no drawing for this character. We checked 147 fonts on a normal machine and 127 of them include it. The character itself is always correct; only the drawing is missing.