tabular column size width not fitting all content

Question

I am using the following code, based on How to use letter with SI unit in table using siunitx to create a table.

How can i make the column wide enouth to fit the content. Whats the best way for the dimensions column setup?

\begin{table}[!htp] % not just 'h!'
\centering % not a center environment
\begin{tabular}{
        @{}
        l
        S[table-format=1.1]
        S[table-format=1.3]
        S[table-format=1.2]
        S[table-format=1.2]
        S[table-format=1.2]
        @{}
    }
    \toprule
    Inductor &
    {$size$} &
    {$inductance$} &
    {$sensitivity$} &
    {$dc resistance d$} &
    {$SRF$}\\
    &
    {(\si{\milli\meter})} &
    {(\si{\milli\henry})} &
    {(\si{\milli\volt\per\ampere\meter})} &
    {(\si{\ohm})} &
    {(\si{\kilo\hertz})} \\
    \midrule
    Premo       &8.6x3x2.7 &18.5 &90 &165 &300  \\
    TDK         &7x12x33   &8.6   &23 &112 &135     \\
    \bottomrule
\end{tabular}
\label{tab:inductor}

\end{table}

Answer 1

At a standard line width, the table is slightly overfull, so I use a tabular* trick; you'll need to check whether this works and the intercolumn space is adequate, otherwise you may resort to \small.

The second column is not S, but you should use \num for its entries. Set properly the number of digits for the other columns.

Please, don't use math mode for italics: it's not meant for that purpose.

\documentclass[a4paper]{article}
\usepackage{amsmath,siunitx,booktabs}

\begin{document}

\begin{table}[htp]
\centering

\setlength{\tabcolsep}{0pt} % let TeX do the calculations
\begin{tabular*}{\textwidth}{
  @{\extracolsep{\fill}}
  l
  c
  S[table-format=2.1]
  S[table-format=2.0]
  S[table-format=3.0]
  S[table-format=3.0]
  @{}
}
\toprule
Inductor &
  {\itshape size} &
  {\itshape inductance} &
  {\itshape sensitivity} &
  {\itshape DC resistance $d$} &
  {\itshape SRF}\\
&
  {(\si{\milli\meter\cubed})} &
  {(\si{\milli\henry})} &
  {(\si{\milli\volt\per\ampere\meter})} &
  {(\si{\ohm})} &
  {(\si{\kilo\hertz})} \\
\midrule
Premo & \num{8.6x3x2.7} & 18.5 & 90 & 165 & 300 \\
TDK   & \num{7x12x33}   &  8.6 & 23 & 112 & 135 \\
\bottomrule
\end{tabular*}

\caption{A table}\label{xyz}

\end{table}

\end{document}

Answer 2

It makes no real sense to use a S column specifier for the size column. However, use the notation {...} if you have not a number in the column cell and, of course, use proper specifications for numbers: 3.1 (iii.d) reserves space for three integers and one decimal

\documentclass[a4paper, 12pt]{article}
\usepackage{amsmath,siunitx,booktabs}

\begin{document}

\begin{tabular}{
        @{}
        l
        S[table-format=1.1]
        S[table-format=2.1]
        S[table-format=2.1]
        S[table-format=3.1]
        S[table-format=3.1]
        @{}
    }
    \toprule
    Inductor &
    {\itshape size} &
    {\itshape inductance} &
    {\itshape sensitivity} &
    {\itshape dc resistance d} &
    {\itshape SRF}\\
    &
    {(\si{\milli\meter})} &
    {(\si{\milli\henry})} &
    {(\si{\milli\volt\per\ampere\meter})} &
    {(\si{\ohm})} &
    {(\si{\kilo\hertz})} \\
    \midrule
    Premo       &{8.6x3x2.7} &18.5 &90 &165 &300  \\
    TDK         &{7x12x33}   &8.6   &23 &112 &135     \\
    \bottomrule
\end{tabular}

\end{document}