Symbol tables (amssymb / lists)

“How do I type this symbol in LaTeX?” — a question you hit constantly once you write mathematics. The toolkit for answering it comes down to about four things. First, the **amssymb package, which supplies most of what standard LaTeX lacks. Next, the Comprehensive LaTeX Symbol List (Scott Pakin), which catalogues some 25,000 symbols by package and by topic. Detexify, where you draw a symbol by hand to find its command. And mathcomp/textcomp**, for upright symbols such as units and temperature in math mode. This page lays out that symbol-finding toolkit — rather than yet another symbol table — and bridges to the detailed per-category lookup pages.

amssymb — the package you load next

When the symbol you want is not in standard LaTeX, **amssymb is the first thing to try**. It is a package from the American Mathematical Society (AMS): a single line, \usepackage{amssymb}, in the preamble unlocks several hundred extra symbols. It is distinct from amsmath — a useful way to keep them straight is that amsmath handles the structure of mathematics (alignment environments, fraction machinery), while amssymb adds the symbols themselves.

A word on the machinery. Loading amssymb internally calls the AMSFonts package amsfonts, which sets up two AMS symbol fonts, msam and msbm. The file amssymb.sty is what gives command names to the glyphs in those fonts. So \usepackage{amssymb} alone also brings in what amsfonts provides — \mathbb (blackboard bold), \mathfrak (Fraktur), and symbols such as \checkmark and \hbar (strictly these are defined on the amsfonts side, but since amssymb loads it, you need not request it separately).

The symbols amssymb adds fall into roughly five families. Keeping them in mind tells you whether your target is likely to live here.

• Extra relations. Variants and cousins of the standard relations: \leqslant (slanted “less-or-equal”) and \geqslant, \lesssim and \gtrsim, the double-lined \subseteqq and \supseteqq, and more.
• Negated relations. Dedicated symbols with a slash already drawn through them: \nleq (not less-or-equal), \ngeq, \nsim, \nsubseteq, \nmid (does not divide), and others.
• Extra arrows. Decorative arrows such as \twoheadrightarrow (two-headed = surjection), \rightrightarrows (side-by-side pair), \rightsquigarrow (squiggly), and \dashrightarrow (dashed).
• Miscellaneous symbols. \varnothing (rounded empty set), \square / \blacksquare, \complement, \nexists, \circledast, and so on.
• Hebrew letters. \beth, \gimel, \daleth (used for cardinals). Note that \aleph alone is already in standard LaTeX.

\usepackage{amssymb}   % 追加の関係子・否定・矢印・雑記号・ヘブライ文字
% ...
\[ 0 \leqslant x \lesssim 1, \qquad a \nmid b, \qquad A \subseteqq B \]
\[ f \colon X \twoheadrightarrow Y, \qquad \varnothing \ne S, \qquad \aleph_0 < \beth_1 \]

amssymb relations and negations (a sampler)

Relation variants and negations are among the most-used families in amssymb. A representative set appears below (not exhaustive; all require amssymb). Setting “less-or-equal” as the slanted \leqslant (⩽) is widely preferred in mathematics, and for negations the dedicated slashed symbols look cleaner than an ad-hoc \not\leq.

A relation with no dedicated negation can be negated on the fly by prefixing **\not** (e.g. \not\equiv). But \not’s slash has a fixed size and slope, so it sits awkwardly over some symbols. **\ne (≠) and \notin (∉) already have dedicated commands in standard LaTeX**, so they need neither amssymb nor \not. The spacing of the relation class, and \not in detail, are covered on the “Relations” page.

amssymb arrows, misc symbols & Hebrew

Here are representative members of the other three families too (all amssymb). Among arrows, the common ones are the two-headed \twoheadrightarrow (↠) for a surjection, the tailed \rightarrowtail (↣) for an injection, and the squiggly \rightsquigarrow (⇝). Among miscellaneous symbols, the staples are the rounded empty set \varnothing (∅), the \square used for the end-of-proof □, and \complement for set complement.

Hebrew letters are used for cardinals (infinite cardinalities) in set theory. Only \aleph (ℵ) is in standard LaTeX; the following **\beth, \gimel, and \daleth require amssymb**. The Greek variants \digamma (ϝ) and \varkappa (ϰ) also come from amssymb (see the Greek page). Exhaustive listings of each family live on the “Arrows,” “Miscellaneous symbols,” and “Relations” pages — this meta page is the doorway that tells you where to look.

The Comprehensive LaTeX Symbol List (the definitive catalogue)

When a symbol is not even in amssymb — or when you need to pin down which package contains it — the definitive reference is The Comprehensive LaTeX Symbol List by Scott Pakin. It arranges the symbols available from LaTeX by package and by topic, and the count has grown edition over edition, reaching about 25,000 as of 2026 (up sharply from roughly 14,600 in 2020). For each symbol it gives the glyph, the command, and the package required, with an index at the back.

It ships with TeX Live and MiKTeX, so you can open it locally without an internet connection. Typing the following in a terminal opens the installed PDF in your viewer. On CTAN it is named comprehensive, and the PDF files are symbols-a4.pdf (A4) and symbols-letter.pdf (letter).

# インストール済みの「記号網羅一覧」を開く / open the installed symbol list
texdoc comprehensive

# ファイル名を直接指定してもよい / or name the file directly
texdoc symbols-a4

The trick is to narrow down from the topic chapters, then confirm the command in the by-package tables. Cross-disciplinary symbols — for electrical circuits, chess pieces, astronomy, and the like — are all in here. Bear in mind, though, that many of the listed symbols require installing a dedicated font or package before you can use them; the list itself states up front that not everything is available in a stock setup. It is distributed under the LPPL (LaTeX Project Public License).

Detexify — draw it to find the command

When you know neither the name nor the field of a symbol but do know its shape, Detexify is the tool. A web app by Daniel Kirsch, it lets you draw a symbol in a box with the mouse or a finger and then offers a ranked list of LaTeX commands whose shapes are closest. For “what is that bent arrow called again?” it can be far faster than scanning a printed list line by line.

Each candidate also shows whether the command is standard LaTeX or which package it needs, such as amssymb. Because it recognizes freehand drawing, it will not always hit on the first try, but telling it which candidate was correct feeds back into the recognition model and improves accuracy over time. The official site is detexify.kirelabs.org. For those who prefer to work locally, a few desktop and mobile apps built on the same idea also exist.

mathcomp / textcomp — upright units & symbols

One more family of tools, easy to forget, is **textcomp and its math-mode counterpart mathcomp**. textcomp enables the extra TS1 (Text Companion) encoding, giving you text-mode symbols such as the degree sign \textdegree (°), per-mille \textperthousand (‰), ohm \textohm (Ω), micro \textmu (µ), and Celsius \textcelsius (℃). In modern LaTeX many of these are folded into the kernel, but older documents or certain fonts may still need it loaded explicitly.

Sometimes, though, you want these symbols inside math mode — for instance, to set the unit “µm” with an upright µ rather than a slanted variable. That is what mathcomp is for: it re-exposes textcomp’s \text… symbols as a set of math-mode commands named \tc… (text companion). The naming rule is simple — replace text with tc, so \textmu becomes \tcmu and \textdegree becomes \tcdegree.

Loading is just \usepackage{mathcomp}, which pulls in textcomp internally. You can pass a font family as an option (e.g. \usepackage[ppl]{mathcomp} to use Palatino’s TC fonts), and \tcdigitoldstyle{0} … \tcdigitoldstyle{9} give old-style figures. Note that \tcohm (Ω) is distinct from the Greek capital \Omega — this is the proper unit symbol. For serious unit typesetting, the dedicated **siunitx** package is often a better fit; that is covered on the “Units (siunitx)” page.