ℝ
ℝ Real Numbers Symbol
ℝ is the set of all real numbers — the blackboard-bold (double-struck) capital R used in math and set theory.
Also known as: all real numbers symbol, real numbers symbol, blackboard bold r, double-struck r.
Codes
| Symbol | ℝ | |
| Unicode | U+211D | |
| HTML entity (named) | ℝ | |
| HTML entity (decimal) | ℝ | |
| HTML entity (hex) | ℝ | |
| CSS | \211D | |
| LaTeX | \mathbb{R} | |
| Windows Alt code | Alt + 8477 |
How to type ℝ (Real Numbers Symbol)
WindowsAlt + 8477
In Microsoft Word, type 211D then Alt + X. In other apps, open the emoji/symbol panel with Win + . (period) and search “double-struck”, or copy from above.
Mac
Open Character Viewer (Control + Cmd + Space), search “double-struck capital r”, and double-click ℝ.
Microsoft Word211D, Alt + X
Type 211D, then press Alt + X to convert it to ℝ.
Google Docs
Insert → Special characters, then search “double-struck” — or inside an Equation type \R.
LaTeX\mathbb{R}
Use \mathbb{R} in math mode — it needs \usepackage{amssymb} (or amsfonts). Plain \R is not defined by default.
Usage
- x ∈ ℝ says that x is a real number; ℝ is every number on the number line, including √2 and π.
- The companion sets are ℕ (U+2115) naturals, ℤ (U+2124) integers, ℚ (U+211A) rationals and ℂ (U+2102) complex numbers.
- Which one to use: in a document, paste the real character ℝ (U+211D) — a bold letter R is not the same thing and will not read as the set of reals. In LaTeX, \mathbb{R} requires amssymb.
- “All real numbers” as an interval is written (−∞, ∞).