terraform fmt command is used to rewrite Terraform configuration files
to a canonical format and style. This command applies a subset of
the Terraform language style conventions,
along with other minor adjustments for readability.
Other Terraform commands that generate Terraform configuration will produce
configuration files that conform to the style imposed by
terraform fmt, so
using this style in your own files will ensure consistency.
The canonical format may change in minor ways between Terraform versions, so
after upgrading Terraform we recommend to proactively run
on your modules along with any other changes you are making to adopt the new
We don't consider new formatting rules in
terraform fmt to be a breaking
change in new versions of Terraform, but we do aim to minimize changes for
configurations that are already following the style examples shown in the
Terraform documentation. When adding new formatting rules, they will usually
aim to apply more of the rules already shown in the configuration examples
in the documentation, and so we recommend following the documented style even
for decisions that
terraform fmt doesn't yet apply automatically.
Formatting decisions are always subjective and so you might disagree with the
terraform fmt makes. This command is intentionally opinionated
and has no customization options because its primary goal is to encourage
consistency of style between different Terraform codebases, even though the
chosen style can never be everyone's favorite.
We recommend that you follow the style conventions applied by
when writing Terraform modules, but if you find the results particularly
objectionable then you may choose not to use this command, and possibly choose
to use a third-party formatting tool instead. If you choose to use a
third-party tool then you should also run it on files that are generated
automatically by Terraform, to get consistency between your hand-written files
and the generated files.
terraform fmt [options] [target...]
fmt scans the current directory for configuration files. If you
provide a directory for the
target argument, then
fmt will scan that
directory instead. If you provide a file, then
fmt will process just that
file. If you provide a single dash (
fmt will read from standard
The command-line flags are all optional. The following flags are available:
-list=false- Don't list the files containing formatting inconsistencies.
-write=false- Don't overwrite the input files. (This is implied by
-checkor when the input is STDIN.)
-diff- Display diffs of formatting changes
-check- Check if the input is formatted. Exit status will be 0 if all input is properly formatted. If not, exit status will be non-zero and the command will output a list of filenames whose files are not properly formatted.
-recursive- Also process files in subdirectories. By default, only the given directory (or current directory) is processed.