# [Tex/LaTex] mathtools vs amsmath

amsmathmath-modemathtools

The mathtools package fixes some amsmath quirks and adds some useful
settings, symbols, and environments to amsmath.

It sounds like "mathtools has everything that amsmath has and more", isn't it?

Are there cases when it is justified to use amsmath instead of mathtools?

In other words: Is mathtools "always" better?

I believe that the answer has been provided, mostly in the comments but here is a short summary:

The mathtools package loads the amsmath package, if it has not already been loaded. This is common in many packages that need to ensure that dependencies are loaded. If you have a look in mathtools.sty line 60, you will see:

  \RequirePackage{amsmath}[2000/07/18]


As such if you only load mathtools, you will have both packages loaded and you do not need to \usepackage{amsmath} in your preamble. To see this you can run the following minimal:

  \documentclass{article}
\usepackage{mathtools}
\makeatletter

Certainly mathtools is not a replacement package for amsmath. This is clear from the package author's comments in the abstract and the introduction: