From ccce414825827615b9f18bbfe65d344d6f828257 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebasti=C3=A1n=20Ram=C3=ADrez?= <tiangolo@gmail.com>
Date: Sat, 21 Feb 2026 09:21:27 +0100
Subject: [PATCH] =?UTF-8?q?=E2=99=BB=EF=B8=8F=20Add=20bytes=20JSON=20Schem?=
 =?UTF-8?q?a=20for=20base64?=
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---
 fastapi/_compat/v2.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fastapi/_compat/v2.py b/fastapi/_compat/v2.py
index 6c3cf2af4c..777a22281f 100644
--- a/fastapi/_compat/v2.py
+++ b/fastapi/_compat/v2.py
@@ -44,6 +44,8 @@ evaluate_forwardref = eval_type_lenient
 class GenerateJsonSchema(_GenerateJsonSchema):
     def bytes_schema(self, schema: CoreSchema) -> JsonSchemaValue:
         json_schema = {"type": "string", "contentMediaType": "application/octet-stream"}
+        if self._config.ser_json_bytes == "base64":
+            json_schema["contentEncoding"] = "base64"
         self.update_with_validations(json_schema, schema, self.ValidationsMapping.bytes)
         return json_schema