diff --git a/Cargo.lock b/Cargo.lock
index 9143f02afb..c91b4e957d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -201,9 +201,9 @@ dependencies = [
 
 [[package]]
 name = "atoi"
-version = "0.4.0"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "616896e05fc0e2649463a93a15183c6a16bf03413a7af88ef1285ddedfa9cda5"
+checksum = "d7c57d12312ff59c811c0643f4d80830505833c9ffaebd193d819392b265be8e"
 dependencies = [
  "num-traits",
 ]
diff --git a/git-index/Cargo.toml b/git-index/Cargo.toml
index dff0245602..87b6fcc909 100644
--- a/git-index/Cargo.toml
+++ b/git-index/Cargo.toml
@@ -44,7 +44,7 @@ bstr = { version = "0.2.13", default-features = false }
 
 serde = { version = "1.0.114", optional = true, default-features = false, features = ["derive"] }
 smallvec = "1.7.0"
-atoi = "0.4.0" # TODO: use 1.0 once edition 2021 is supported in MSRV
+atoi = "1.0.0"
 bitflags = "1.3.2"
 
 document-features = { version = "0.2.0", optional = true }