diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 6880f84d9d..67a3101bde 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -374,10 +374,7 @@ int8_t step_to_accuracy_decimals(float step) {
 }
 
 // Store BASE64 characters as array - automatically placed in flash/ROM on embedded platforms
-static const char BASE64_CHARS[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
-                                    'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
-                                    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
-                                    'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};
+static const char BASE64_CHARS[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
 // Helper function to find the index of a base64 character in the lookup table.
 // Returns the character's position (0-63) if found, or 0 if not found.