diff --git a/crates/ruma-client-api/src/r0/media/create_content.rs b/crates/ruma-client-api/src/r0/media/create_content.rs
index fe0abc34..f7a86b85 100644
--- a/crates/ruma-client-api/src/r0/media/create_content.rs
+++ b/crates/ruma-client-api/src/r0/media/create_content.rs
@@ -26,6 +26,16 @@ ruma_api! {
         /// The content type of the file being uploaded.
         #[ruma_api(header = CONTENT_TYPE)]
         pub content_type: Option<&'a str>,
+
+        /// Should the server return a blurhash or not.
+        ///
+        /// This uses the unstable prefix in
+        /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+        #[ruma_api(query)]
+        #[cfg(feature = "unstable-pre-spec")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+        #[serde(rename = "xyz.amorgan.blurhash")]
+        pub generate_blurhash: bool,
     }
 
     response: {
@@ -49,7 +59,13 @@ ruma_api! {
 impl<'a> Request<'a> {
     /// Creates a new `Request` with the given file contents.
     pub fn new(file: &'a [u8]) -> Self {
-        Self { file, filename: None, content_type: None }
+        Self {
+            file,
+            filename: None,
+            content_type: None,
+            #[cfg(feature = "unstable-pre-spec")]
+            generate_blurhash: false,
+        }
     }
 }
 
diff --git a/crates/ruma-client-api/src/r0/profile/get_avatar_url.rs b/crates/ruma-client-api/src/r0/profile/get_avatar_url.rs
index eceb77ed..4a21fc8e 100644
--- a/crates/ruma-client-api/src/r0/profile/get_avatar_url.rs
+++ b/crates/ruma-client-api/src/r0/profile/get_avatar_url.rs
@@ -30,7 +30,17 @@ ruma_api! {
             feature = "compat",
             serde(default, deserialize_with = "ruma_serde::empty_string_as_none")
         )]
-        pub avatar_url: Option<MxcUri>
+        pub avatar_url: Option<MxcUri>,
+
+        /// The [BlurHash](https://blurha.sh) for the avatar pointed to by `avatar_url`.
+        ///
+        /// This uses the unstable prefix in
+        /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+        #[cfg(feature = "unstable-pre-spec")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+        #[serde(rename = "xyz.amorgan.blurhash")]
+        #[serde(skip_serializing_if = "Option::is_none")]
+        pub blurhash: Option<String>,
     }
 
     error: crate::Error
@@ -46,6 +56,10 @@ impl<'a> Request<'a> {
 impl Response {
     /// Creates a new `Response` with the given avatar URL.
     pub fn new(avatar_url: Option<MxcUri>) -> Self {
-        Self { avatar_url }
+        Self {
+            avatar_url,
+            #[cfg(feature = "unstable-pre-spec")]
+            blurhash: None,
+        }
     }
 }
diff --git a/crates/ruma-client-api/src/r0/profile/get_profile.rs b/crates/ruma-client-api/src/r0/profile/get_profile.rs
index 94a500a9..00ca2fbb 100644
--- a/crates/ruma-client-api/src/r0/profile/get_profile.rs
+++ b/crates/ruma-client-api/src/r0/profile/get_profile.rs
@@ -35,6 +35,16 @@ ruma_api! {
         /// The user's display name, if set.
         #[serde(skip_serializing_if = "Option::is_none")]
         pub displayname: Option<String>,
+
+        /// The [BlurHash](https://blurha.sh) for the avatar pointed to by `avatar_url`.
+        ///
+        /// This uses the unstable prefix in
+        /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+        #[cfg(feature = "unstable-pre-spec")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+        #[serde(rename = "xyz.amorgan.blurhash")]
+        #[serde(skip_serializing_if = "Option::is_none")]
+        pub blurhash: Option<String>,
     }
 
     error: crate::Error
@@ -50,6 +60,11 @@ impl<'a> Request<'a> {
 impl Response {
     /// Creates a new `Response` with the given avatar URL and display name.
     pub fn new(avatar_url: Option<MxcUri>, displayname: Option<String>) -> Self {
-        Self { avatar_url, displayname }
+        Self {
+            avatar_url,
+            displayname,
+            #[cfg(feature = "unstable-pre-spec")]
+            blurhash: None,
+        }
     }
 }
diff --git a/crates/ruma-client-api/src/r0/profile/set_avatar_url.rs b/crates/ruma-client-api/src/r0/profile/set_avatar_url.rs
index 026f9021..6206c409 100644
--- a/crates/ruma-client-api/src/r0/profile/set_avatar_url.rs
+++ b/crates/ruma-client-api/src/r0/profile/set_avatar_url.rs
@@ -37,6 +37,16 @@ ruma_api! {
             serde(skip_serializing_if = "Option::is_none")
         )]
         pub avatar_url: Option<&'a MxcUri>,
+
+        /// The [BlurHash](https://blurha.sh) for the avatar pointed to by `avatar_url`.
+        ///
+        /// This uses the unstable prefix in
+        /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+        #[cfg(feature = "unstable-pre-spec")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+        #[serde(rename = "xyz.amorgan.blurhash")]
+        #[serde(skip_serializing_if = "Option::is_none")]
+        pub blurhash: Option<&'a str>,
     }
 
     #[derive(Default)]
@@ -48,7 +58,12 @@ ruma_api! {
 impl<'a> Request<'a> {
     /// Creates a new `Request` with the given user ID and avatar URL.
     pub fn new(user_id: &'a UserId, avatar_url: Option<&'a MxcUri>) -> Self {
-        Self { user_id, avatar_url }
+        Self {
+            user_id,
+            avatar_url,
+            #[cfg(feature = "unstable-pre-spec")]
+            blurhash: None,
+        }
     }
 }
 
@@ -75,7 +90,7 @@ mod tests {
                     .uri("https://bar.org/_matrix/client/r0/profile/@foo:bar.org/avatar_url")
                     .body(&[] as &[u8]).unwrap(),
             ).unwrap(),
-            IncomingRequest { user_id, avatar_url: None } if user_id == "@foo:bar.org"
+            IncomingRequest { user_id, avatar_url: None, .. } if user_id == "@foo:bar.org"
         );
 
         #[cfg(feature = "compat")]
@@ -87,7 +102,7 @@ mod tests {
                     .body(serde_json::to_vec(&serde_json::json!({ "avatar_url": "" })).unwrap())
                     .unwrap(),
             ).unwrap(),
-            IncomingRequest { user_id, avatar_url: None } if user_id == "@foo:bar.org"
+            IncomingRequest { user_id, avatar_url: None, .. } if user_id == "@foo:bar.org"
         );
     }
 }
diff --git a/crates/ruma-events/src/room/member.rs b/crates/ruma-events/src/room/member.rs
index d07a0daa..2f8916e6 100644
--- a/crates/ruma-events/src/room/member.rs
+++ b/crates/ruma-events/src/room/member.rs
@@ -69,6 +69,16 @@ pub struct MemberEventContent {
     /// contain information about that invitation.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub third_party_invite: Option<ThirdPartyInvite>,
+
+    /// The [BlurHash](https://blurha.sh) for the avatar pointed to by `avatar_url`.
+    ///
+    /// This uses the unstable prefix in
+    /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+    #[cfg(feature = "unstable-pre-spec")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+    #[serde(rename = "xyz.amorgan.blurhash")]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub blurhash: Option<String>,
 }
 
 impl MemberEventContent {
@@ -80,6 +90,8 @@ impl MemberEventContent {
             displayname: None,
             is_direct: None,
             third_party_invite: None,
+            #[cfg(feature = "unstable-pre-spec")]
+            blurhash: None,
         }
     }
 }
@@ -227,6 +239,8 @@ fn membership_change(
             is_direct: None,
             membership: St::Leave,
             third_party_invite: None,
+            #[cfg(feature = "unstable-pre-spec")]
+            blurhash: None,
         }
     };
 
@@ -326,6 +340,7 @@ mod tests {
                     is_direct: None,
                     membership: MembershipState::Join,
                     third_party_invite: None,
+                    ..
                 },
                 event_id,
                 origin_server_ts,
@@ -372,6 +387,7 @@ mod tests {
                     is_direct: None,
                     membership: MembershipState::Join,
                     third_party_invite: None,
+                    ..
                 },
                 event_id,
                 origin_server_ts,
@@ -385,6 +401,7 @@ mod tests {
                     is_direct: None,
                     membership: MembershipState::Join,
                     third_party_invite: None,
+                    ..
                 }),
             } if event_id == "$h29iv0s8:example.com"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(1))
@@ -439,6 +456,7 @@ mod tests {
                         display_name: third_party_displayname,
                         signed: SignedContent { mxid, signatures, token },
                     }),
+                    ..
                 },
                 event_id,
                 origin_server_ts,
@@ -510,6 +528,7 @@ mod tests {
                     is_direct: None,
                     membership: MembershipState::Join,
                     third_party_invite: None,
+                    ..
                 },
                 event_id,
                 origin_server_ts,
@@ -526,6 +545,7 @@ mod tests {
                         display_name: third_party_displayname,
                         signed: SignedContent { mxid, signatures, token },
                     }),
+                    ..
                 }),
             } if event_id == "$143273582443PhrSn:example.org"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(233))
@@ -586,6 +606,7 @@ mod tests {
                     is_direct: None,
                     membership: MembershipState::Join,
                     third_party_invite: None,
+                    ..
                 },
                 event_id,
                 origin_server_ts,
@@ -602,6 +623,7 @@ mod tests {
                         display_name: third_party_displayname,
                         signed: SignedContent { mxid, signatures, token },
                     }),
+                    ..
                 }),
             } if event_id == "$143273582443PhrSn:example.org"
                 && origin_server_ts == MilliSecondsSinceUnixEpoch(uint!(233))
diff --git a/crates/ruma-federation-api/src/query/get_profile_information/v1.rs b/crates/ruma-federation-api/src/query/get_profile_information/v1.rs
index 18b9b587..9d42fb18 100644
--- a/crates/ruma-federation-api/src/query/get_profile_information/v1.rs
+++ b/crates/ruma-federation-api/src/query/get_profile_information/v1.rs
@@ -41,6 +41,16 @@ ruma_api! {
             serde(default, deserialize_with = "ruma_serde::empty_string_as_none")
         )]
         pub avatar_url: Option<MxcUri>,
+
+        /// The [BlurHash](https://blurha.sh) for the avatar pointed to by `avatar_url`.
+        ///
+        /// This uses the unstable prefix in
+        /// [MSC2448](https://github.com/matrix-org/matrix-doc/pull/2448).
+        #[cfg(feature = "unstable-pre-spec")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "unstable-pre-spec")))]
+        #[serde(rename = "xyz.amorgan.blurhash")]
+        #[serde(skip_serializing_if = "Option::is_none")]
+        pub blurhash: Option<String>,
     }
 }