diff --git a/src/molify/compress.py b/src/molify/compress.py
index 8de448c..20b1316 100644
--- a/src/molify/compress.py
+++ b/src/molify/compress.py
@@ -18,7 +18,7 @@ def compress(
     atoms : ase.Atoms
         The Atoms object to compress.
     density : float
-        The target density in g/cm^3.
+        The target density in kg/m^3.
     freeze_molecules : bool
         If True, freeze the internal degrees of freedom of the molecules
         during compression, to prevent bond compression.