diff --git a/Sources/GeoHashFramework/GeoHash.swift b/Sources/GeoHashFramework/GeoHash.swift
index 053631a..c260ade 100644
--- a/Sources/GeoHashFramework/GeoHash.swift
+++ b/Sources/GeoHashFramework/GeoHash.swift
@@ -10,7 +10,7 @@ public struct GeoHash: Sendable, Hashable {
 
     /// Base32 characters used to hash
     ///
-    // a and o are omitted
+    // a, i, l and o are omitted
     package static let base32Chars = "0123456789bcdefghjkmnpqrstuvwxyz"
 
     /// Create a GeoHash from a string.