Summation Symbol (∑)
The summation symbol ∑ is Unicode U+2211, the sigma of summation notation. Press Copy to put it on your clipboard, or type it with Option + W on a Mac.
- Unicode
U+2211- HTML
∑- Word
2211 Alt+X- Mac
Option + W
How to type the summation symbol (∑)
The quickest way is to press Copy above and paste. To type ∑ yourself, use the method for your device below. On a Mac it is Option + W.
Windows
- In Word or Outlook, type 2211 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 N-Ary Summation, then Select and Copy. Character Map is built into every version of Windows.
Mac
- Press Option+W. On the standard US and US-International layouts.
- Press Control + Command + Space to open the Character Viewer, search for summation and double-click it.
Linux & ChromeOS
- Press Ctrl + Shift + U, type 2211, then press Enter or Space. Works in GTK and IBus apps (GNOME, Firefox, Chrome, LibreOffice) and on ChromeOS.
iPhone & iPad
- Copy ∑ from this page, then go to Settings → General → Keyboard → Text Replacement and add it with a shortcut such as ;summ. The shortcut then turns into the symbol as you type, in every app.
Android
- Copy ∑ here, then open Gboard settings → Dictionary → Personal dictionary and add it with a shortcut.
Microsoft Word
- Type 2211, then press Alt + X.
- Insert → Symbol → More Symbols. Set “from” to Unicode (hex), type 2211 in “Character code” and click Insert.
- On a Mac, Option+W works in Word too.
Google Docs
- Insert → Special characters, then search for “summation” or draw it in the box.
Excel & Google Sheets
- Enter
=UNICHAR(8721)in a cell. It works in Excel 2013 and later and in Google Sheets.
HTML
- Write
∑or∑in your HTML.
What does ∑ mean?
∑ means “add up”. Written with an index and limits, it compresses a long sum into one line: ∑ from i = 1 to n of i equals 1 + 2 + … + n = n(n + 1)/2. Leonhard Euler popularised the capital sigma for sums in the 18th century, and it is now standard in maths, statistics and computing.
Unicode distinguishes the operator ∑ (N-ARY SUMMATION) from the Greek capital letter Σ. They can look identical, but ∑ is designed to be larger and to carry limits above and below, while Σ is a letter of the alphabet. Use ∑ in formulas and Σ in Greek words or where sigma is a variable, such as Σ for a covariance matrix.
In spreadsheets the symbol is only a label; the function is =SUM(). In statistics you will see it inside formulas for the mean, x̄ = (∑xᵢ)/n, and the variance.
Common uses
- Series: ∑ 1/2ⁿ = 1
- Statistics: mean = ∑x / n
- AutoSum buttons and “total” labels in apps
Summation Symbol codes for HTML, CSS and programming
Every code below produces ∑. Use the HTML entity in web pages, the CSS escape in content, and the escape sequence in source code.
| Unicode code point | U+2211 | |
|---|---|---|
| HTML entity (named) | ∑ | |
| HTML decimal | ∑ | |
| HTML hex | ∑ | |
| CSS content | content: "\2211"; | |
| JavaScript | "\u2211" | |
| Python | "\u2211" | |
| Python (by name) | "\N{N-ARY SUMMATION}" | |
| Java / C# | "\u2211" | |
| LaTeX | \sum | |
| UTF-8 bytes | E2 88 91 | |
| UTF-16 | 2211 | |
| URL encoded | %E2%88%91 | |
| Mac shortcut | Option + W |
∑ vs look-alike characters
These characters look similar to ∑ 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 capital SigmaU+03A3 | Greek capital letter sigma. A letter, used in Greek text and as a variable name. | |
N-Ary ProductU+220F | N-ary product, the multiplication counterpart of ∑. | |
Double-Struck N-Ary SummationU+2140 | Double-struck n-ary summation, a rare variant. |
Symbols similar to ∑
Click to copy, or open a symbol for its codes. See the full math symbols collection.
- Greek capital Sigma Details
- N-Ary Product Details
- Integral Details
- Minus Details
- Multiplication Details
- Division Details
- Plus-Minus Details
- Not Equal to Details
- Almost Equal to Details
- Identical to Details
- Less-Than Or Equal to Details
- Greater-Than Or Equal to Details
- Proportional to Details
- Infinity Details
- Per Mille Details
∑ character properties
- Official Unicode name
- N-ARY SUMMATION
- Also known as
- sigma notation, sum symbol, n-ary summation, sum sign
- Code point
- U+2211
- Unicode block
- Mathematical Operators (U+2200–U+22FF)
- General category
- Math symbol (Sm)
- Added in
- Unicode 1.1 (1993)
- Plane
- Basic Multilingual Plane (0)
- Emoji
- No, it is a text symbol
Frequently asked questions
Is the summation symbol the same as sigma?
They look alike, but they are different characters. ∑ (U+2211) is the summation operator; Σ (U+03A3) is the Greek letter. Use ∑ in equations.
What is the sum symbol in Excel?
Excel uses the SUM function, =SUM(A1:A10), and the AutoSum button shows ∑ as its icon.
Is there an alt code for the summation symbol?
No. ∑ is outside the Windows-1252 and code page 437 character sets, so no Alt + number code produces it. Copy it from this page, type 2211 then Alt + X in Word, or find it in Character Map.
How do I type the summation symbol on a Mac?
Press Option + W. It works in every app on the US keyboard layout. You can also open the Character Viewer with Control + Command + Space and search for it.
What is the HTML code for the summation symbol?
Use the named entity ∑ or the numeric reference ∑ (hex ∑). All three display ∑ in every browser.
What is the Unicode for the summation symbol?
∑ is U+2211, officially named N-ARY SUMMATION, in the Mathematical Operators block. It has been part of Unicode since version 1.1 (1993).