-sa (set Archive name mode) switch

Specifies Archive name mode.

Syntax

-sa[a | e | s]

Switch	Description
-saa	Always add archive type extension.
-sae	Use exact name specified in command.
-sas	Add extension only if specified name has no extension. It's default option.

Examples

  7z a arc 1.txt

creates arc.7z

  7z a arc.spec 1.txt

creates arc.spec

  7z a arc 1.txt -sae

creates arc

  7z a file.pdf file.pdf -saa -tzip

creates file.pdf.zip

Commands that can be used with this switch

a (Add),

Notes from this site

Not part of the 7-Zip manual. Written by this site; examples checked with 7-Zip 26.04.

Why does my archive have no .7z extension?

The default (-sas) treats anything after the last dot as an extension, and a dotted date looks like one. The archive is then written under exactly the name you typed, so double-clicking it may not open 7-Zip. On Linux and macOS the official console binary is 7zz; on Windows it is 7z.

What goes wrong: this writes a 7z archive named exactly backup.2026.10.13.

7zz a backup.2026.10.13 files/

The fix is -saa, which always adds the extension of the archive type. Without -t the type is 7z; with -tzip you get .zip.

7zz a backup.2026.10.13 files/ -saa
7zz a backup.2026.10.13 files/ -saa -tzip
7zz a "backup-$(date +%F)" files/ -saa

These create backup.2026.10.13.7z, backup.2026.10.13.zip and, on the day of testing, backup-2026-10-13.7z. Use -saa in backup scripts, since dotted dates are the usual trigger. The $(date +%F) form is for Linux and macOS; on Windows write the date into the name yourself. Do not use -saa with a name that already ends in .7z: 7zz a x.7z docs/ -saa creates x.7z.7z.

Good to know

This switch applies to the a (Add) command only.
The archive type comes from -t, never from the name: -sae -tzip makes a zip with no extension.
To open an archive made with -sae, rename it or use File > Open in the 7-Zip File Manager.

-t (Type of archive)