Pi — π Greek Letter Symbol
π
Pi — π / Π
16th letter of the Greek alphabet · pronounced /paɪ/
MathematicsPhysicsEngineeringGeometry
Copy symbol
π
Lowercase pi
Π
Uppercase Pi
Technical reference
| Unicode (lowercase) | U+03C0 |
| Unicode (uppercase) | U+03A0 |
| HTML entity | π |
| HTML decimal | π |
| LaTeX | \pi |
| Python / Unicode escape | \u03c0 |
| Alt code (Windows) | Alt + 960 |
Uses in science & engineering
Circle constant
Ratio of a circle circumference to its diameter. One of the most fundamental constants in mathematics.
\(\pi \approx 3.14159265\ldots\)
Area and volume formulas
Appears in formulas for circles, spheres, cylinders — essential in all engineering disciplines.
\(A = \pi r^2 \qquad V = \frac{4}{3}\pi r^3\)
Euler formula
Connects the five most important constants in mathematics.
\(e^{i\pi} + 1 = 0\)
Product notation (Π)
Uppercase Pi denotes the product of a sequence, analogous to Σ for summation.
\(\prod_{i=1}^{n} x_i = x_1 \cdot x_2 \cdots x_n\)
Pi theorem (dimensional analysis)
Buckingham Pi theorem: fundamental tool for dimensional analysis in fluid mechanics.
\(f(\pi_1, \pi_2, \ldots, \pi_k) = 0\)
Related symbols
How to insert in applications
Windows
Best option: copy from this page.
Or press Win + . to open emoji & symbols panel.
Alt codes work only in Word/Notepad with NumLock on and English layout — not in browsers.
Or press Win + . to open emoji & symbols panel.
Alt codes work only in Word/Notepad with NumLock on and English layout — not in browsers.
macOS
Press ⌃⌘Space → Character Viewer → search “pi”
Microsoft Word
Type 03c0 then press Alt+X
Google Docs
Insert → Special characters → search by name
Excel
Insert → Symbol → Subset: Greek → select symbol
LaTeX
Use in math mode: $ … $
Python
Use Unicode escape or chr()
HTML / CSS
Use HTML entity or decimal code