Iterate through dates

There's an old package, that temporarily sets the date with \AdvanceDate.

\documentclass{article}

\usepackage{pgffor}
\usepackage{advdate}


\begin{document}
\ThisDay{0} % Set the day number to zero
\ThisMonth{1} % Start in January
%\ThisYear{2017} % for example
\foreach \x in {1,...,365} {%
  \AdvanceDate[\x]
  {\hfill\huge\textbf{\today}\hfill}  % Just as an example
  \clearpage
}

\end{document}

As can be seen from the screen shot the \AdvanceDate command is aware of leap years