diff --git a/Cargo.toml b/Cargo.toml
index 204a04b..d5ae6fd 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,7 @@ all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
 
 [dependencies]
-hifitime = { version = "3.9", optional = true }
+hifitime = { version = "4.0", optional = true }
 once_cell = { version = "1.19", optional = true }
 regex = { version = "1.7", optional = true }
 reqwest = { version = "0.12", optional = true }