diff --git a/cargo-typify/src/lib.rs b/cargo-typify/src/lib.rs
index 0e592d45..b94e311f 100644
--- a/cargo-typify/src/lib.rs
+++ b/cargo-typify/src/lib.rs
@@ -100,7 +100,8 @@ impl std::str::FromStr for CrateSpec {
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         fn is_crate(s: &str) -> bool {
-            !s.contains(|cc: char| !cc.is_alphabetic() && cc != '-' && cc != '_')
+            s.starts_with(|cc: char| cc.is_alphabetic() || cc == '_')
+                && !s.contains(|cc: char| !cc.is_alphanumeric() && cc != '-' && cc != '_')
         }
 
         fn convert(s: &str) -> Option<CrateSpec> {
diff --git a/typify-macro/src/lib.rs b/typify-macro/src/lib.rs
index d68ba325..69b74026 100644
--- a/typify-macro/src/lib.rs
+++ b/typify-macro/src/lib.rs
@@ -159,7 +159,8 @@ impl<'de> Deserialize<'de> for CrateName {
 }
 
 fn is_crate(s: &str) -> bool {
-    !s.contains(|cc: char| !cc.is_alphanumeric() && cc != '_' && cc != '-')
+    s.starts_with(|cc: char| cc.is_alphabetic() || cc == '_')
+        && !s.contains(|cc: char| !cc.is_alphanumeric() && cc != '_' && cc != '-')
 }
 
 #[derive(Deserialize)]