diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index e44b9e549e..5ad4caef2a 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -553,38 +553,36 @@ static inline bool is_base64(char c) { return (isalnum(c) || (c == '+') || (c ==
 
 std::string base64_encode(const std::vector<uint8_t> &buf) { return base64_encode(buf.data(), buf.size()); }
 
+// Encode 3 input bytes to 4 base64 characters, append 'count' to ret.
+static inline void base64_encode_triple_(const char *char_array_3, int count, std::string &ret) {
+  char char_array_4[4];
+  char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
+  char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
+  char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
+  char_array_4[3] = char_array_3[2] & 0x3f;
+
+  for (int j = 0; j < count; j++)
+    ret += BASE64_CHARS[static_cast<uint8_t>(char_array_4[j])];
+}
+
 std::string base64_encode(const uint8_t *buf, size_t buf_len) {
   std::string ret;
   int i = 0;
-  int j = 0;
   char char_array_3[3];
-  char char_array_4[4];
 
   while (buf_len--) {
     char_array_3[i++] = *(buf++);
     if (i == 3) {
-      char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
-      char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
-      char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
-      char_array_4[3] = char_array_3[2] & 0x3f;
-
-      for (i = 0; (i < 4); i++)
-        ret += BASE64_CHARS[static_cast<uint8_t>(char_array_4[i])];
+      base64_encode_triple_(char_array_3, 4, ret);
       i = 0;
     }
   }
 
   if (i) {
-    for (j = i; j < 3; j++)
+    for (int j = i; j < 3; j++)
       char_array_3[j] = '\0';
 
-    char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
-    char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
-    char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
-    char_array_4[3] = char_array_3[2] & 0x3f;
-
-    for (j = 0; (j < i + 1); j++)
-      ret += BASE64_CHARS[static_cast<uint8_t>(char_array_4[j])];
+    base64_encode_triple_(char_array_3, i + 1, ret);
 
     while ((i++ < 3))
       ret += '=';
@@ -597,7 +595,7 @@ size_t base64_decode(const std::string &encoded_string, uint8_t *buf, size_t buf
   return base64_decode(reinterpret_cast<const uint8_t *>(encoded_string.data()), encoded_string.size(), buf, buf_len);
 }
 
-// Decode 4 base64 characters to up to 'count' output bytes, returns true if truncated
+// Decode 4 base64 characters to up to 'count' output bytes, returns true if truncated.
 static inline bool base64_decode_quad_(uint8_t *char_array_4, int count, uint8_t *buf, size_t buf_len, size_t &out) {
   for (int i = 0; i < 4; i++)
     char_array_4[i] = base64_find_char(char_array_4[i]);