Delta Symbol (Δ δ ∆): How to Type It Everywhere

Short answer: Tap a delta below to copy it. To type it: on Windows, Alt + 916 = Δ, Alt + 948 = δ (numeric keypad); on Mac, Option + J = ∆, or use the Character Viewer for Greek Δ/δ; in Word, type 0394 then Alt + X; in HTML use Δ / δ; in LaTeX use \Delta / \delta.

Delta is the fourth Greek letter — see the whole set in the Greek alphabet guide or get any letter’s codes from the Alt Code Finder.

Delta (Δ uppercase, δ lowercase) is the fourth letter of the Greek alphabet, and in maths and science it famously means “change” or “difference” — ΔT is a change in temperature, Δx a change in x. But there are actually three near-identical symbols people mix up, so let’s clear that up first.

Δ vs ∆ vs ∂ — which one do you need?

Three characters look alike but are different:

Δ — Greek capital delta (U+0394). Use this in text, for Greek, and it’s fine for “change in” too.
∆ — the increment sign (U+2206). Visually identical to Δ, but encoded specifically for the mathematical meaning “change / finite difference.” It’s what a Mac types with Option + J.
∂ — partial differential (U+2202), the “curly d.” This is not a delta — it’s used for partial derivatives (∂z/∂x) and is often mistaken for lowercase δ. On a Mac, Option + D produces it.

In practice, for everyday writing Δ works everywhere; reach for ∆ only if a style guide or maths tool specifically wants the increment character, and never confuse δ with ∂.

Greek delta, the increment sign and the partial derivative compared

Quick reference

Symbol	Name	Windows	Mac	HTML	LaTeX	Unicode
Δ	Greek capital delta	Alt + 916	Viewer / Greek input	`Δ`	`\Delta`	U+0394
δ	Greek small delta	Alt + 948	Viewer / Greek input	`δ`	`\delta`	U+03B4
∆	Increment	Alt + 8710	Option + J	`∆`	`\Delta`	U+2206

Type delta on Windows

Alt codes: hold Alt, type on the numeric keypad (Num Lock on): Alt + 916 → Δ, Alt + 948 → δ. Works in Unicode-aware apps (Word, browsers, email).
Word: type 0394 and press Alt + X for Δ, or 03B4 + Alt + X for δ. In an equation (Alt + =), type \Delta or \delta then Space.
Lots of Greek: add the Greek keyboard (Settings → Time & language → Language) and switch with Windows + Space.

Type delta on Mac

∆ (increment): press Option + J — the quickest delta on a Mac.
Greek Δ / δ: open the Character Viewer with Control + Command + Space, search “delta,” and double-click the uppercase or lowercase form; or add the Greek input source.
Watch out: Option + D gives ∂ (partial derivative), not a delta — don’t use it for δ.

Delta in Word & Excel

Word: the 0394 + Alt + X method above, or Insert → Symbol → (Greek and Coptic).
Excel: the Alt + X trick doesn’t work in Excel, so use Insert → Symbol, type 0394 in the “Character code” box (with “from: Unicode (hex)”), and Insert — or just paste Δ from the tool above. For a delta inside a cell’s number, a custom format or a small text label is the usual workaround.

Delta in HTML & LaTeX

HTML: Δ → Δ, δ → δ; numeric fallbacks Δ / δ (or hex Δ / δ) render the same.
LaTeX (math mode): \Delta for Δ, \delta for δ. The increment/Laplacian is also just \Delta; the partial derivative is \partial.

Type delta on Linux & phone

Linux: Ctrl + Shift + U, then 0394 (Δ) or 03b4 (δ), then Enter.
Phone: add a Greek keyboard (iPhone: Settings → General → Keyboard; Android: Gboard languages) and switch with the globe key, or copy δ/Δ from the tool above.

What delta means

Delta is one of the busiest symbols in STEM:

Change or difference — Δx, Δt, ΔT (the classic use), and ΔV, Δp elsewhere.
Discriminant — Δ = b² − 4ac in the quadratic formula.
Laplace operator — Δ (= ∇²) in differential equations.
Uncertainty — Δ for measurement error or spread.
Chemistry — Δ over a reaction arrow means “heat applied,” and ΔH is a change in enthalpy.
Finance — “delta” is an options Greek: how much an option’s price moves per unit change in the underlying.
Lowercase δ — the Kronecker delta δᵢⱼ, the Dirac delta δ(x), and small quantities/variations.
Elsewhere — a river delta (its triangular shape), and the set-theory symmetric difference A △ B.

Troubleshooting

Problem	Fix
Alt + 916 gives the wrong character	Use the numeric keypad with Num Lock on, in a Unicode-aware app; basic editors may not support it.
Δ shows as a box ▯	Font lacks the glyph — switch to Segoe UI, Arial or Cambria Math. See symbol showing as a box.
Alt + X doesn’t work in Excel	Excel has no Alt + X — use Insert → Symbol (code 0394) or paste.
I got ∂ instead of δ on Mac	Option + D is the partial-derivative sign; use the Character Viewer for Greek δ.
Δ vs ∆ look different in my font	They’re separate characters (U+0394 vs U+2206); pick one and stay consistent.

Recap

Windows → Alt + 916 (Δ) / Alt + 948 (δ); Word: 0394 + Alt + X.
Mac → Option + J (∆); Character Viewer for Greek Δ/δ.
Web → Δ / δ. LaTeX → \Delta / \delta.
Excel → Insert → Symbol (0394) or paste.

Frequently asked questions

What does the delta symbol mean?

Delta is the fourth letter of the Greek alphabet, written Δ (uppercase) and δ (lowercase). In maths and science it usually means “change” or “difference” — for example ΔT is a change in temperature and Δx a change in x. It also stands for the discriminant, the Laplace operator, and enthalpy change (ΔH), among others.

What’s the difference between Δ and ∆?

They look identical but are different Unicode characters: Δ (U+0394) is the Greek capital letter delta, while ∆ (U+2206) is the mathematical increment sign, encoded specifically for “change / finite difference.” For everyday writing, Δ works fine; use ∆ only if a tool or style guide specifically wants the increment character.

How do I type delta on Windows?

Hold Alt and type 916 on the numeric keypad for Δ, or 948 for δ, in a Unicode-aware app. In Word, you can also type 0394 (or 03B4) and press Alt + X. For lots of Greek, add the Greek keyboard layout and switch with Windows + Space.

How do I type delta on a Mac?

Press Option + J for the increment delta ∆. For the Greek capital Δ or lowercase δ, open the Character Viewer with Control + Command + Space and search “delta,” or add the Greek input source. Note that Option + D gives ∂ (partial derivative), not a delta.

How do I insert the delta symbol in Excel?

Excel doesn’t support the Alt + X method, so use Insert → Symbol, type 0394 in the “Character code” box with “from: Unicode (hex),” and click Insert — or simply copy Δ and paste it into the cell.

Is δ the same as ∂ (the partial derivative)?

No. δ is the Greek small letter delta (U+03B4); ∂ is the partial differential sign (U+2202), a stylised cursive “d” used for partial derivatives. They look somewhat similar but are different characters with different meanings, so don’t substitute one for the other.

Written by Igor R.. Tested on Windows 11, macOS, Word, Excel and LaTeX. Symbol code points follow the Unicode Standard. Last updated July 2026.