Theta Symbol (θ)
The theta symbol θ is Unicode U+03B8, the Greek letter most used for angles. Press Copy to put it on your clipboard.
- Unicode
U+03B8- HTML
θ- Word
03B8 Alt+X
How to type the theta symbol (θ)
The quickest way is to press Copy above and paste. To type θ yourself, use the method for your device below.
Windows
- In Word or Outlook, type 03B8 and press Alt + X. Alt + X converts the hex code before the cursor into the character, and back again.
- Press Win + R, type charmap and press Enter. Tick “Advanced view”, search for Greek Small Letter Theta, then Select and Copy. Character Map is built into every version of Windows.
Mac
- Press Control + Command + Space to open the Character Viewer, search for theta and double-click it.
- With the Unicode Hex Input keyboard enabled (System Settings → Keyboard → Input Sources), hold Option and type 03B8.
Linux & ChromeOS
- Press Ctrl + Shift + U, type 3b8, then press Enter or Space. Works in GTK and IBus apps (GNOME, Firefox, Chrome, LibreOffice) and on ChromeOS.
iPhone & iPad
- Copy θ from this page, then go to Settings → General → Keyboard → Text Replacement and add it with a shortcut such as ;thet. The shortcut then turns into the symbol as you type, in every app.
Android
- Copy θ here, then open Gboard settings → Dictionary → Personal dictionary and add it with a shortcut.
Microsoft Word
- Type 03B8, then press Alt + X.
- Insert → Symbol → More Symbols. Set “from” to Unicode (hex), type 03B8 in “Character code” and click Insert.
Google Docs
- Insert → Special characters, then search for “theta” or draw it in the box.
Excel & Google Sheets
- Enter
=UNICHAR(952)in a cell. It works in Excel 2013 and later and in Google Sheets.
HTML
- Write
θorθin your HTML.
What does θ mean?
Theta (θ, capital Θ) is the eighth letter of the Greek alphabet, pronounced “THAY-tuh”. It represents the “th” sound, and linguists borrowed it for exactly that: in the phonetic alphabet, θ is the sound at the start of “thin”.
In maths and physics θ is the default name for an angle. You meet it in trigonometry (sin θ, cos θ), in polar coordinates (r, θ), and in physics problems about slopes and pendulums. Statisticians use θ for an unknown parameter, and in computer science Θ-notation (“big theta”) describes the exact growth rate of an algorithm. The capital Θ has the CP437 alt code Alt + 233; the lowercase has no alt code, so use 03B8 and Alt + X in Word.
Common uses
- Trigonometry: tan θ = opposite / adjacent
- Polar coordinates: x = r cos θ
- Algorithms: merge sort runs in Θ(n log n)
- Phonetics: /θɪn/ for “thin”
Theta Symbol codes for HTML, CSS and programming
Every code below produces θ. Use the HTML entity in web pages, the CSS escape in content, and the escape sequence in source code.
| Unicode code point | U+03B8 | |
|---|---|---|
| HTML entity (named) | θ | |
| HTML decimal | θ | |
| HTML hex | θ | |
| CSS content | content: "\3B8"; | |
| JavaScript | "\u03B8" | |
| Python | "\u03B8" | |
| Python (by name) | "\N{GREEK SMALL LETTER THETA}" | |
| Java / C# | "\u03B8" | |
| LaTeX | \theta | |
| UTF-8 bytes | CE B8 | |
| UTF-16 | 03B8 | |
| URL encoded | %CE%B8 |
θ vs look-alike characters
These characters look similar to θ but have a different meaning and code. Pasting the wrong one can break search, sorting and screen readers.
| Char | Name | When to use it |
|---|---|---|
Greek Theta SymbolU+03D1 | Greek theta symbol (U+03D1), a cursive variant preferred in some maths texts. | |
Greek capital ThetaU+0398 | Greek capital Theta (U+0398), used in big-theta notation. | |
Latin Letter Bilabial ClickU+0298 | Latin letter bilabial click (U+0298). It looks like a circle with a dot, not a bar. | |
Empty SetU+2205 | Empty set (U+2205). A circle with a slash, often confused with a slashed θ in handwriting. | |
Capital O with StrokeU+00D8 | Latin capital O with stroke, a letter in Danish and Norwegian. |
Symbols similar to θ
Click to copy, or open a symbol for its codes. See the full greek letters collection.
- Greek Alpha Details
- Greek Beta Details
- Greek Gamma Details
- Greek Epsilon Details
- Greek Zeta Details
- Greek Eta Details
- Greek Iota Details
- Greek Kappa Details
- Greek Lamda Details
- Greek Mu Details
- Greek Nu Details
- Greek Xi Details
- Greek Omicron Details
- Greek Pi Details
- Greek Rho Details
- Greek Tau Details
- Greek Upsilon Details
- Greek Phi Details
θ character properties
- Official Unicode name
- GREEK SMALL LETTER THETA
- Also known as
- theta, greek letter theta, angle symbol theta
- Code point
- U+03B8
- Unicode block
- Greek and Coptic (U+0370–U+03FF)
- General category
- Lowercase letter (Ll)
- Added in
- Unicode 1.1 (1993)
- Plane
- Basic Multilingual Plane (0)
- Emoji
- No, it is a text symbol
Frequently asked questions
What does θ mean in maths?
θ usually names an angle, especially in trigonometry and polar coordinates. In statistics it can also stand for an unknown parameter.
Is there a keyboard shortcut for theta?
Not for the lowercase on Windows or Mac. In Word, type 03B8 and press Alt + X. The capital Θ can be typed with Alt + 233.
Is there an alt code for the theta symbol?
No. θ is outside the Windows-1252 and code page 437 character sets, so no Alt + number code produces it. Copy it from this page, type 03B8 then Alt + X in Word, or find it in Character Map.
How do I type the theta symbol on a Mac?
There is no single Option shortcut for θ on the US layout. Press Control + Command + Space to open the Character Viewer, search for “theta” and double-click it, or copy it from this page.
What is the HTML code for the theta symbol?
Use the named entity θ or the numeric reference θ (hex θ). All three display θ in every browser.
What is the Unicode for the theta symbol?
θ is U+03B8, officially named GREEK SMALL LETTER THETA, in the Greek and Coptic block. It has been part of Unicode since version 1.1 (1993).