Delta Symbol (Δ)

Copy the delta symbol Δ or the small delta δ with one click below. In math and science, Δ means “change in”, so Δt is a change in time. On a Mac, Option + J types ∆, and on Windows, Alt + 235 types the small δ.

Delta symbol codes

These are the delta signs and their lookalikes, with the HTML code and the Windows Alt code. Each sign in the tool above also shows its Unicode number.

Sign	HTML	Alt
Δ Capital delta	Δ	None
δ Small delta	δ	235
∆ Increment	∆	None
∇ Nabla	∇	None
𝚫 Bold math delta	𝚫	None
△ Triangle	△	None

Capital Δ has no Alt code. Alt + 235 works for the small δ only, with no zero in front. For Δ on Windows, copy it from this page or use one of the ways below. Our Alt Code Finder lists every code that does exist.

How to type the delta symbol

Windows

Press Windows key + . (period), click the Ω tab and look through the symbol lists for Δ. If you type Greek often, add the Greek keyboard in Settings > Time & language > Language & region. Then Shift + D gives Δ and D gives δ.

Mac

Press Option + J to get ∆. Strictly speaking this is the increment sign (U+2206), not the Greek letter, but it looks the same and works for notes and homework. For the true Greek Δ, press Control + Command + Space and search for “delta”. Our Mac symbols guide has more shortcuts.

Microsoft Word

Type 0394 and press Alt + X for Δ, or 03B4 and Alt + X for δ. In an equation (Alt + =), type \Delta or \delta and press Space. The capital D in \Delta is what makes the letter capital.

Google Docs

Go to Insert > Symbols > Special characters and search for “delta”. In an equation, \Delta works the same way as in Word. See our Google Docs guide for more.

Excel and Google Sheets

=UNICHAR(916) gives Δ and =UNICHAR(948) gives δ. A handy trick for reports is a change column, like ="Δ "&TEXT(B2-A2,"0.0"), which shows Δ 4.5 for the difference between two cells.

iPhone and Android

Add the Greek keyboard (Settings > General > Keyboard > Keyboards on iPhone, or Gboard settings > Languages on Android), then switch with the globe key. Or simply copy Δ from this page.

Chromebook

Press Ctrl + Shift + U, type 394, then press Space or Enter.

HTML, CSS and LaTeX

In HTML, use Δ for Δ and δ for δ. In CSS, use content: "\0394";. In LaTeX, \Delta gives Δ, \delta gives δ and \nabla gives ∇.

What does the delta symbol mean?

In math and science, capital Δ means “the change in”. If the temperature goes from 20°C to 25°C, then ΔT = 25 − 20 = 5°C. You will also see it as Δx for a change in position and Δt for a change in time, so speed is Δx ÷ Δt.

Δ has a few other jobs too. In algebra, Δ = b² − 4ac is the discriminant, which tells you how many answers a quadratic equation has. In chemistry, ΔH is the heat change of a reaction, and a small Δ written over the reaction arrow means heat is added.

Small δ usually means a very small change, or a value close to zero. It also has fixed meanings in some fields, like the Dirac delta in physics and declination in astronomy.

Δ, ∆, ∇ or △: which one do you need?

Sign	Use it for
Δ	The Greek letter, and “change in” for most school and science work
∆	The math increment sign from Mac Option + J, looks the same as Δ
∇	Nabla, the gradient in calculus and physics
△	A triangle in geometry, as in △ABC

For most people, Δ and ∆ are interchangeable, since they look the same in almost every font. Use △ when you mean a triangle shape. Our triangle symbols page has more of those.

Why a river delta is called a delta

The flat land where a big river splits up before the sea is called a delta because of this letter. The mouth of the Nile spreads out in a rough triangle, just like Δ, and the Greek historian Herodotus used the name about 2,500 years ago.

Frequently asked questions

Is there an Alt code for the delta symbol?

Not for capital Δ. Alt + 235 gives the small δ. For Δ, press Windows key + . (period) or copy it from this page.

How do I type delta on a Mac?

Press Option + J. It gives ∆, which looks the same as the Greek Δ.

What does Δ mean in math?

It means “change in”. Δy is the change in y, so the slope of a line is Δy ÷ Δx.

What is the difference between Δ and δ?

Δ is the capital letter and usually means a measurable change. δ is the small letter and usually means a tiny change, or has a special meaning in a field like physics.

What is the HTML code for delta?

Δ or Δ for Δ, and δ or δ for δ.

Sources: the Unicode Greek and Coptic chart (U+0394) and the Mathematical Operators chart (U+2206, U+2207). Written by Muhammad Ilyas, updated October 2026.

More Greek and math signs: all Greek letters, pi π, infinity ∞ and all math symbols in one place.