Phi Symbol (φ)

Phi (φ) is the Greek letter tied to the golden ratio ≈ 1.618 — the proportion found in art, shells and sunflowers.

Greek Small Letter Phi · U+03C6 · Greek Letters

Click the symbol or the button to copy it, then paste it anywhere — documents, messages, bios and code.

Phi Symbol codes

Code	Value
Unicode code point	`U+03C6`
Unicode name	`Greek Small Letter Phi`
HTML named entity	`φ`
HTML decimal	`φ`
HTML hex	`φ`
CSS content code	`\3C6`
JavaScript / JSON	`\u03C6`
Windows Alt code	No standard Alt code — copy it from the card above
LaTeX	`\phi`

Phi Symbol variants (4)

4 related glyphs — click any tile to copy it. Tiles with a page open that symbol's own page.

ΦGreek Capital Letter PhiϕGreek Phi SymbolθGreek Small Letter Theta ψGreek Small Letter Psi

Meaning & usage

φ became famous as the symbol of the golden ratio, the 'divine proportion' ≈ 1.618 that appears in nautilus shells, sunflower seeds and Renaissance art. Mathematicians also use φ for Euler's totient function and for angles alongside θ, and physicists use it for magnetic flux and wave functions. The capital Φ is a different-looking letter entirely — a circle with a vertical stroke — so check the variants if you need that form.

Examples in use

The golden ratio φ ≈ 1.618
A φ of 45° in spherical coordinates
φ(n) counts numbers coprime to n

How to type the phi symbol

Windows

There is no Alt code or direct key for φ. In Microsoft Word, type 03C6 and press Alt+X to convert it. Everywhere else, click the Copy button at the top of this page and paste it (Ctrl+V) — that always works.

Mac

There is no Option-key shortcut for φ on a Mac. Open the Character Viewer with Control+Command+Space, search for "Phi Symbol", and double-click to insert — or copy it from this page.

iPhone & Android

Most phone keyboards have no built-in key for φ. Open this page on your phone, tap Copy, then paste it into your message or bio. (On Android, Gboard's emoji search finds some symbols by name.)

Linux

Press Ctrl+Shift+U, type 03c6 and press Enter (works in most GTK apps and terminals with IBus). Or copy it from this page.

Frequently asked questions

How do I type φ on a keyboard?

There is no standard Alt code. Copy φ from this page; in Word, type 03C6 then press Alt+X.

Is φ pronounced 'fee' or 'fie'?

In Greek it is 'fee'; many English-speaking mathematicians say 'fie'. Both are understood — 'fee' is closer to the original.

Why does φ sometimes show as a box or question mark?

The box (called tofu) means the device or font viewing it has no drawing for U+03C6 (Greek Small Letter Phi). The character itself is fine — try a different font or a newer device, or use one of the variants on this page.

Is the Phi Symbol free to use?

Yes. φ is a standard Unicode text character published in the Unicode Character Database. You may use it in personal and commercial documents, designs and products without permission or payment.

Related symbols

θTheta Symbol αAlpha Symbol