diff --git a/.github/workflows/ci-version.yml b/.github/workflows/ci-version.yml
index 0972e45..b5706c2 100644
--- a/.github/workflows/ci-version.yml
+++ b/.github/workflows/ci-version.yml
@@ -60,7 +60,7 @@ jobs:
           - macos-latest
           - windows-latest
         toolchain:
-          - "1.70"
+          - "1.60"
         features:
           -
           - --features u128
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4bf8ea4..b36a48a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -76,7 +76,7 @@ jobs:
           - macos-latest
           - windows-latest
         toolchain:
-          - "1.70"
+          - "1.60"
         features:
           -
           - --features u128
diff --git a/Cargo.toml b/Cargo.toml
index 8d94864..c076797 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,7 +3,7 @@ name = "byte-unit"
 version = "5.0.0-beta.1"
 authors = ["Magic Len <len@magiclen.org>"]
 edition = "2021"
-rust-version = "1.70"
+rust-version = "1.60"
 repository = "https://github.com/magiclen/byte-unit"
 homepage = "https://magiclen.org/byte-unit"
 keywords = ["byte", "unit", "kb", "mb", "gb"]