diff --git a/include/libpsl.h.in b/include/libpsl.h.in
index 4a49804..ff34a65 100644
--- a/include/libpsl.h.in
+++ b/include/libpsl.h.in
@@ -155,7 +155,7 @@ const char *
 int
 	psl_check_version_number(int version);
 
-/* returns wether the built-in data is outdated or not */
+/* returns whether the built-in data is outdated or not */
 int
 	psl_builtin_outdated(void);
 
diff --git a/src/lookup_string_in_fixed_set.c b/src/lookup_string_in_fixed_set.c
index 9baa990..2f68bd7 100644
--- a/src/lookup_string_in_fixed_set.c
+++ b/src/lookup_string_in_fixed_set.c
@@ -30,7 +30,7 @@ static const char multibyte_length_table[16] = {
 
 
 /**
- * Get lenght of multibyte character sequence starting at a given byte.
+ * Get length of multibyte character sequence starting at a given byte.
  * Returns zero if the byte is not a valid leading byte in UTF-8.
  */
 static int GetMultibyteLength(char c) {
diff --git a/src/psl.c b/src/psl.c
index 4e6aa14..72892ab 100644
--- a/src/psl.c
+++ b/src/psl.c
@@ -1284,7 +1284,7 @@ void psl_free(psl_ctx_t *psl)
  * psl_builtin:
  *
  * This function returns the PSL context that has been generated and built in at compile-time.
- * You don't have to free the returned context explicitely.
+ * You don't have to free the returned context explicitly.
  *
  * The builtin data also contains punycode entries, one for each international domain name.
  *