The Sigma symbol (Σ) is widely used in mathematics, statistics, and science to represent summation, among other things. On this website, you’ll learn about its meaning, how to use it in different contexts, and how to easily copy or type the Sigma symbol. Explore our detailed guide to unlock the power of Sigma in your work.

ς
Greek small letter final sigma

ͻ
Greek reversed lunate sigma symbol

Ͻ
Greek capital reversed lunate sigma symbol

∑
N-ary summation

⅀
Double-struck N-ary summation

ϛ
Greek small letter stigma

Ϛ
Greek capital letter stigma

𝚺
Mathematical bold capital sigma

𝛔
Mathematical bold small sigma

𝜮
Mathematical italic capital sigma

𝝈
Mathematical italic small sigma

𝞢
Mathematical bold italic capital sigma

𝞼
Mathematical bold italic small sigma

Σx
Sum of x

Σ(x)
Sum of function x

Σᵢ
Sigma with subscript i

Σⁿ
Sigma with superscript n

∑∑
Double summation

∑∑∑
Triple summation

σ²
Sigma squared variance

σx
Standard deviation of x

Σf(x)Δx
Riemann sum

Σ→∫
Summation approaches integral

∑
Summation

𝚺
Capital Letter Sigma

𝛔
Small Letter Sigma

𝞢
Mathematical Sans-Serif Capital Sigma

𝞨
Mathematical Sans-Serif Bold Capital Sigma

𝞼
Mathematical Sans-Serif Small Sigma

Ϻ
Greek Capital Letter Sigma

Ꜭ
Latin Letter Small Sigma

Ȿ
Latin Capital Sigma

σ
Greek Small Letter Sigma

Ⓢ
Circled Uppercase Sigma

ⓢ
Circled Lowercase Sigma

𝗦
Bold Uppercase Sigma

𝘀
Bold Lowercase Sigma

𝚺
Double-Struck Capital Sigma

𝚼
Double-Struck Lowercase Sigma

𝕾
Bold Fraktur Capital Sigma

𝔖
Mathematical Fraktur Capital Sigma

ₛ
Subscript Sigma

ˢ
Superscript Sigma

𝒮
Sigma-algebra

𝓢
Cursive Sigma

Σ(x)
Sigma Function

σ-bond
Sigma Bond

σ′
Sigma Prime

∑≈
Sigma Approximation

⨑
Summation Symbol

𝞭
Sigma Completion

σ→
Sigma Substitution

lim Σ
Sigma Limit

∫Σ
Sigma Integral

Σn
Sigma Notation

∮Σ
Integral over Sigma

𝛛Σ
Partial Sigma

ⵒ
Inverted Summation

𝓕(Σ)
Sigma Field

ℓΣ
Sigma Form

∑=
Sigma Calculation

𝜮⃗
Vector Sigma

⨖
Capital Sigma Dotted

σ✚
Lowercase Sigma Crossed

⟶Σ
Sigma Transition

Σ−
Sigma Minus

Σ+
Sigma Plus

σ⋅
Sigma Dot

σ•
Sigma Bullet

σ|
Sigma Bar

Σ/
Sigma Slash

σ⊂
Sigma Subset

Σ⊃
Sigma Superset

σ∈
Sigma Membership

ΣΔ
Sigma Difference

𝒯(Σ)
Sigma Topology

σₘₐₜ
Sigma Matrix

σ̃
Sigma Wave

σΓ
Sigma Gamma

ΣΠ
Sigma Pi

ΣΤ
Sigma Tau

ΣΠ(x)
Summation of Products

Σexp(x)
Summation of Exponentials

Σκ
Sigma Kappa

Σ(r,θ)
Sigma Polar Coordinates

Σ^2
Sigma to the Power

σ(p)
Sigma Prime Number

∫Σ(x)
Sigma Calculus

Σgeom
Sigma Geometry

Σ(T)
Sigma Topology Equation

Σₛₑᵣ
Sigma Series

Σₑₓₚ
Sigma Series Expansion

Σₜᵢₘₑ
Sigma Time Series

σ⋅p
Sigma Point

σ∂
Sigma Boundary

Σ∬
Sigma Double Integral

ΣΔT
Sigma Triangle

σ(x,y)
Sigma Multivariate

Σₙ
Sigma Closed Form

∮ΣP
Sigma Closed Path

σ=const
Sigma as a Constant

Σ(A)
Sigma Analysis

Σop
Sigma Operator

∮Σ(x)
Sigma Path Integral

σ∠
Sigma Rotation

The Unicode for the uppercase Sigma symbol (Σ) is U+03A3, and for the lowercase sigma (σ), it is U+03C3. Unicode allows consistent representation of characters across digital platforms. You can use these codes to insert the Sigma symbol in HTML, XML, and other digital formats, ensuring compatibility across different systems and applications.

The Sigma symbol (Σ) is the 18th letter of the Greek alphabet and is widely recognized for its use in mathematics, statistics, and various scientific fields. In mathematics, the uppercase Sigma (Σ) typically represents summation, a process of adding a sequence of numbers or expressions together to achieve a total. In statistics, lowercase sigma (σ) represents the standard deviation, a key concept that describes the spread or variability in a data set. Sigma also has uses in physics, engineering, and probability theory.

To type the Sigma symbol (Σ) on a Windows computer, press the 'Alt' key and type 228 on the numeric keypad for uppercase Σ. For lowercase σ, type 229. On a Mac, use Option (⌥) + W for Σ and Option (⌥) + S for σ. On smartphones or tablets, you can access the Sigma symbol by holding down the 'S' key on iPhones or going to the 'Symbols' section on Android. Copying the symbol from this page and pasting it is also an option.

In mathematics, the Sigma symbol (Σ) represents summation, which involves adding up a series of numbers or expressions. It is used extensively in calculus, algebra, and statistics to denote the sum of a sequence. In science and engineering, Sigma often denotes the sum of forces, energy, or probabilities. Lowercase sigma (σ) is used in statistics to represent standard deviation, a measure of the spread of data points around the mean.

On an iPhone or iPad, you can find the Sigma symbol by holding down the 'S' key on the virtual keyboard until the Sigma option appears. On Android devices, Sigma can be found in the 'Symbols' section of the keyboard or by downloading third-party apps that offer Greek letters. You can also copy the symbol from a webpage or document and paste it wherever needed.

Uppercase Sigma (Σ) is used in mathematics to represent summation, a process of adding a sequence of numbers. Lowercase sigma (σ) is used in statistics to denote standard deviation, which measures the spread or variability of data. Both symbols originate from the Greek alphabet but serve distinct functions in their respective fields.