diff --git a/openmls/src/ciphersuite/mac.rs b/openmls/src/ciphersuite/mac.rs
index 5547e7a163..94976ecab0 100644
--- a/openmls/src/ciphersuite/mac.rs
+++ b/openmls/src/ciphersuite/mac.rs
@@ -13,7 +13,7 @@ pub struct Mac {
 
 impl std::fmt::Debug for Mac {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:x?}", self.mac_value.as_slice())
+        write!(f, "{}", hex::encode(self.mac_value.as_slice()))
     }
 }
 
diff --git a/openmls/src/ciphersuite/signature.rs b/openmls/src/ciphersuite/signature.rs
index 7a463b262d..d70b8912c7 100644
--- a/openmls/src/ciphersuite/signature.rs
+++ b/openmls/src/ciphersuite/signature.rs
@@ -9,7 +9,7 @@ use super::{LABEL_PREFIX, *};
 
 /// Signature.
 #[derive(
-    PartialEq, Eq, Clone, Serialize, Deserialize, TlsDeserialize, TlsSerialize, TlsSize,
+PartialEq, Eq, Clone, Serialize, Deserialize, TlsDeserialize, TlsSerialize, TlsSize,
 )]
 pub struct Signature {
     value: VLBytes,
@@ -17,7 +17,7 @@ pub struct Signature {
 
 impl std::fmt::Debug for Signature {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:x?}", self.value.as_slice())
+        write!(f, "{}", hex::encode(self.value.as_slice()))
     }
 }
 
@@ -60,7 +60,7 @@ impl From<(&str, &[u8])> for SignContent {
 
 /// A public signature key.
 #[derive(
-    Eq, PartialEq, Hash, Clone, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
+Eq, PartialEq, Hash, Clone, Serialize, Deserialize, TlsSerialize, TlsDeserialize, TlsSize,
 )]
 pub struct SignaturePublicKey {
     pub(in crate::ciphersuite) value: VLBytes,
@@ -68,7 +68,7 @@ pub struct SignaturePublicKey {
 
 impl std::fmt::Debug for SignaturePublicKey {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:x?}", self.value.as_slice())
+        write!(f, "{}", hex::encode(self.value.as_slice()))
     }
 }
 
diff --git a/openmls/src/extensions/external_pub_extension.rs b/openmls/src/extensions/external_pub_extension.rs
index 6067ae4aff..8387c5d21e 100644
--- a/openmls/src/extensions/external_pub_extension.rs
+++ b/openmls/src/extensions/external_pub_extension.rs
@@ -19,7 +19,7 @@ pub struct ExternalPubExtension {
 
 impl std::fmt::Debug for ExternalPubExtension {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:x?}", self.external_pub.as_slice())
+        write!(f, "{}", hex::encode(self.external_pub.as_slice()))
     }
 }
 
diff --git a/openmls/src/treesync/node/encryption_keys.rs b/openmls/src/treesync/node/encryption_keys.rs
index 2cd20adf24..e8cb07e5c7 100644
--- a/openmls/src/treesync/node/encryption_keys.rs
+++ b/openmls/src/treesync/node/encryption_keys.rs
@@ -29,7 +29,7 @@ pub struct EncryptionKey {
 
 impl std::fmt::Debug for EncryptionKey {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{:x?}", self.key.as_slice().to_vec())
+        write!(f, "{}", hex::encode(self.key.as_slice().to_vec()))
     }
 }