How to enumerate footnotes with circled numbers?

Question

Introduction

Here we collect different solutions to enumerate footnotes with circled numbers both in texts and footnotes for which advantages and disadvantages are specified.

In fact, it’s Chinese who usually enumerate the footnotes with circled numbers, and in Chinese, every circled number has the width of 1em as the same as every Chinese character. Anyway, any solution is welcome.

A MWE is as follows.

\documentclass{article}

\begin{document}
\par Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}.
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}. 
Now we test the footnote numbers with two digits\footnote{Test}.
\end{document}

Summary

So far as now we have five solutions as follows which have their own advantages and disadvantages.

Answer 1

Update:

After discussion with OP, I have an updated solution, still using TikZ.

Add this to the preamble:

\newcommand{\fnrad}{.16}

\usepackage{scrextend,tikz,scalerel}
\newcommand\circled[2][\fnrad]{\kern.5pt\scalerel*{\tikz{\useasboundingbox (-#1,-#1) rectangle (#1,#1);\node{#2};\draw circle[radius=#1];}}{X}\kern.5pt}
\deffootnotemark{\textsuperscript{\smash{\circled{\thefootnotemark}}}}

The command \circled uses scalerel to produce a circled number the same height as a capital letter X, which adjusts if the X changes in size (e.g., titles, superscripts, \large).

The global constant \fnrad (currently set to .16) can be adjusted to create more space around the number without changing the size of the circle. Larger value produces more space. That spacing can also be adjusted with an optional argument in case the footnote appears in special positions like a title:

\large 1\circled{1}\circled[.18]{1}

Advantages:

• Doesn't affect line spacing in text or in footnotes.
• Uses original font.
• Adjusts for font changes and size changes.

Disadvantages:

• Is using TikZ a disadvantage?

Old Solution:

Add this to the preamble:

\usepackage{scrextend,tikz}
\newcommand\circled[1]{\tikz[baseline]{\node[anchor=base,rounded corners=.375em,draw,inner sep=1pt] {#1};}}
\deffootnotemark{\textsuperscript{\smash{\circled{\thefootnotemark}}}}

Advantages: Easy. Doesn't affect line spacing in text or in footnotes. Uses original font.

Disadvantages: Uses TikZ (is that a disadvantage?). Might have to adjust rounded corners for different font. Ovals for 2-digit numbers.

---

Remarks

• The scrextend package is used to enable other packages to use components of KOMA-Script.
• More about the smash command can be read here: What does \smash do, and where is it documented?.

Answer 2

One way to do this without TikZ would be to use predefined Unicode glyphs for circled numbers: ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ⑩. Font support varies, though, so care must be taken to use a font that actually supports the glyphs. I have used Arial Unicode in my example (which, due to the use of fontspec also requires either XeLaTeX or LuaLaTeX.)

\documentclass{article}

\usepackage{fontspec}
% Make sure your font supports circled numbers (U+24EA .. U+32BF)
\setmainfont{ArialUni.ttf}

\makeatletter
\newcommand*{\myfootnote}[1]{% Redefine footnote symbols:
  \ensuremath{%
    \ifcase#1% 0
      \or ① \or ② \or ③ \or ④ \or ⑤%
      \or ⑥ \or ⑦ \or ⑧ \or ⑨ \or ⑩%
% Toying with Chinese circled numbers (Ideographs ≥ U+3280)
%     \or ㊀ \or ㊁ \or ㊂ \or ㊃ \or ㊄
%     \or ㊅ \or ㊆ \or ㊇ \or ㊈ \or ㊉
      \or ⑪ \or ⑫ \or ⑬ \or ⑭ \or ⑮%
      \or ⑯ \or ⑰ \or ⑱ \or ⑲ \or ⑳%
      \or ㉑ \or ㉒ \or ㉓ \or ㉔ \or ㉕%
% can be extended as needed for up to ㊿
    \else \@ctrerr%
    \fi
  }%
}
\makeatother

% Redefine \footnote command:
\renewcommand*{\thefootnote}{\myfootnote{\value{footnote}}}

\begin{document}

Now we test the single-digit footnote numbers.\footnote{Test Nr.\,1}\par
Now we test the single-digit footnote numbers.\footnote{Test Nr.\,2}\par
Now we test the single-digit footnote numbers.\footnote{Test Nr.\,3}\par

\setcounter{footnote}{9}% Skip a few footnotes
\vspace{1em}% Add some vertical space

Now we test footnote numbers with two digits.\footnote{Test Nr.\,10}\par
Now we test footnote numbers with two digits.\footnote{Test Nr.\,11}\par
Now we test footnote numbers with two digits.\footnote{Test Nr.\,12}\par

\end{document}

Although I have used ① .. ㉕ in my example, arbitrary symbols would work just as well.

Addendum: If we need to support both \usepackage[no-math]{fontspec} and Chinese characters, the following might work:

\documentclass{article}

\usepackage[no-math]{fontspec}
\setmainfont{ArialUni.ttf}

\usepackage{xeCJK}
\setCJKmainfont{SimHei.ttf}

\makeatletter
\newcommand*{\myfootnote}[1]{% Redefine footnote symbols:
    \ifcase#1% 0
      \or ① \or ② \or ③ \or ④ \or ⑤%
      \or ⑥ \or ⑦ \or ⑧ \or ⑨ \or ⑩%
      \or ⑪ \or ⑫ \or ⑬ \or ⑭ \or ⑮%
      \or ⑯ \or ⑰ \or ⑱ \or ⑲ \or ⑳%
      \or ㉑ \or ㉒ \or ㉓ \or ㉔ \or ㉕%
    \else \@ctrerr%
    \fi
}
\makeatother

% Redefine \footnote command:
\renewcommand*{\thefootnote}{\myfootnote{\value{footnote}}}

\begin{document}

你好，这是一个测试文档。\footnote{Test Nr.\,1}\par

Now we test the single-digit footnote numbers.\footnote{Test Nr.\,2}\par
\setcounter{footnote}{9}% Skip a few footnotes
\vspace{1em}% Add some vertical space

Now we test footnote numbers with two digits.\footnote{Test Nr.\,10}\par

\end{document}

(It uses the standard article class instead of ctexart, which may or may not be acceptable.)

Answer 3

Here I give three solutions: the first one appears in June, 2011 and is the best choice before the second and third ones come out in April, 2022; the second and third ones are improved versions of the usual solution by the tikz package.

1. By the pifont package

• Due to: @Leo Liu (Cf. the link in which the solution appears at first)
• Recommendation Index: ★★★★
• Advantages: (1) enumerate footnotes with circled roman or sans serif numbers which has beautiful appearances and suitable sizes; (2) you can compiles the file in LaTeX, PDFLaTeX, XeTeX, XeLaTeX, LuaLaTeX and so on.
• Disadvantages: (1) the number font is not in the computer modern series, or can't be the same as the font you are using; (2) the number can't be greater than 10, otherwise their appearances would be different.

It may be the most popular solution right now before the second and third solutions as follows come out, since the number of footnotes on one page is usually no more than 10. Its codes and testing output are as follows.

\documentclass{article}
\usepackage{pifont}%for circled numbers
%%%enumerate footnotes with circled numbers%%%%%%
\renewcommand\thefootnote{\ding{\numexpr171+\value{footnote}}}%roman
%\renewcommand\thefootnote{\ding{\numexpr191+\value{footnote}}}%sans serif
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\par Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. 
\end{document}

2. By the tikz, graphics, etoolbox and microtype packages

• Due to: @M. Logic and @CarLaTeX (Cf. the link)
• Recommendation Index: ★★★★★
• Advantages: (1) enumerate footnotes with circled roman or bfseries or itshape or sffamily or ttfamily numbers which has beautiful appearances and suitable sizes; (2) the number font is in the computer modern series, or could be the same as the font which is collected in the TeX system; (3) the number could be greater than 10 and less than 100.
• Disadvantages: (1) you can compiles the file only in LaTeX and PDFLaTeX because of the use of the microtype package; (2) you should adjust the parameters with different fonts.

It's important to scale the width of two-digit numbers with a suitable value and decrease the spacing of two-digit numbers in the solution. It may be one of the best choices, since the number of footnotes on one page can't be more than 99. Its codes, circled numbers from 0 to 99, and testing output are as follows.

\documentclass{article}
\usepackage{tikz}
\usepackage{graphics}%for \scalebox
\usepackage{etoolbox}%for \ifnumcomp
\usepackage{microtype}%for \textls
%%%define circled command%%%%%%%%%%%%%%
\tikzset{circlednode/.style={
    circle,
    draw,
    inner sep=0.05ex,
    text depth=0ex,
    font=\normalfont,
    minimum size=1ex
    }
}
\newcommand*\circled[1]{%
    \ifnumcomp{#1}{>}{9}{% 
    % if > 9:
    \tikz[baseline=(char.base)]\node[circlednode] (char) {\textls[-70]{\scalebox{0.5}[1]{\bfseries#1}}};}{%
    % if <= 9: 
    \tikz[baseline=(char.base)]\node[circlednode] (char) {#1};}%
}
%%%footnote numbers setting%%%%%%%%%%%%%%%
\makeatletter
%make footnote numbers be circled------------------
\renewcommand{\thefootnote}{%
    \raisebox{0.25ex}{%
    \scalebox{0.7}{\protect\circled{%
            \arabic{footnote}}%
        }%
    }%
}
\makeatother
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\par Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}.
\end{document}

3. By the tikz, graphics, etoolbox and fontspec packages

• Due to: @M. Logic and @CarLaTeX (Cf. the link)
• Recommendation Index: ★★★★★
• Advantages: (1) enumerate footnotes with circled roman or bfseries or itshape or sffamily or ttfamily numbers which has beautiful appearances and suitable sizes; (2) the number font could be the same as the font which is installed on your computer; (3) the number could be greater than 10 and less than 100.
• Disadvantages: (1) you can compiles the file only in XeTeX, XeLaTeX and LuaLaTeX because of the use of the fontspec package; (2) you must set the main font which could be identified by the fontspec package; (3) you should adjust the parameters with different fonts.

It's important to scale the width of two-digit numbers with a suitable value and decrease the spacing of two-digit numbers in the solution. It may be one of the best choices, since the number of footnotes on one page can't be more than 99. Its codes, circled numbers from 0 to 99, and testing output are as follows.

\documentclass{article}
\usepackage{tikz}
\usepackage{graphics}%for \scalebox
\usepackage{etoolbox}%for \ifnumcomp
\usepackage{fontspec}%for \addfontfeature
\setmainfont{Arial}
%%%define circled command%%%%%%%%%%%%%%
\tikzset{circlednode/.style={
    circle,
    draw,
    inner sep=0.05ex,
    text depth=0ex,
    font=\normalfont,
    minimum size=1ex
    }
}
\newcommand*\circled[1]{%
    \ifnumcomp{#1}{>}{9}{% 
    % if > 9:
    \tikz[baseline=(char.base)]\node[circlednode] (char) {\addfontfeature{LetterSpace=-9.0}\scalebox{0.5}[1]{\bfseries#1}};}{%
    % if <= 9: 
    \tikz[baseline=(char.base)]\node[circlednode] (char) {#1};}%
}
%%%footnote numbers setting%%%%%%%%%%%%%%%
\makeatletter
%make footnote numbers be circled------------------
\renewcommand{\thefootnote}{%
    \raisebox{0.25ex}{%
    \scalebox{0.7}{\protect\circled{%
            \arabic{footnote}}%
        }%
    }%
}
\makeatother
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\par Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}. Now we test the footnote numbers with two digits\footnote{Test}.
\end{document}