diff --git a/jwt-authorizer/src/authorizer.rs b/jwt-authorizer/src/authorizer.rs
index c4c8a3f..00d0840 100644
--- a/jwt-authorizer/src/authorizer.rs
+++ b/jwt-authorizer/src/authorizer.rs
@@ -64,7 +64,14 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::RS256, Algorithm::RS384, Algorithm::RS512],
+                        algs: vec![
+                            Algorithm::RS256,
+                            Algorithm::RS384,
+                            Algorithm::RS512,
+                            Algorithm::PS256,
+                            Algorithm::PS384,
+                            Algorithm::PS512,
+                        ],
                         key,
                     })),
                     claims_checker,
@@ -77,7 +84,14 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::RS256, Algorithm::RS384, Algorithm::RS512],
+                        algs: vec![
+                            Algorithm::RS256,
+                            Algorithm::RS384,
+                            Algorithm::RS512,
+                            Algorithm::PS256,
+                            Algorithm::PS384,
+                            Algorithm::PS512,
+                        ],
                         key,
                     })),
                     claims_checker,
@@ -90,7 +104,7 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::ES256, Algorithm::ES384],
+                        algs: vec![Algorithm::ES256, Algorithm::ES384],
                         key,
                     })),
                     claims_checker,
@@ -103,7 +117,7 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::ES256, Algorithm::ES384],
+                        algs: vec![Algorithm::ES256, Algorithm::ES384],
                         key,
                     })),
                     claims_checker,
@@ -116,7 +130,7 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::EdDSA],
+                        algs: vec![Algorithm::EdDSA],
                         key,
                     })),
                     claims_checker,
@@ -129,7 +143,7 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::EdDSA],
+                        algs: vec![Algorithm::EdDSA],
                         key,
                     })),
                     claims_checker,
@@ -142,7 +156,7 @@ where
                 Authorizer {
                     key_source: KeySource::SingleKeySource(Arc::new(KeyData {
                         kid: None,
-                        alg: vec![Algorithm::HS256, Algorithm::HS384, Algorithm::HS512],
+                        algs: vec![Algorithm::HS256, Algorithm::HS384, Algorithm::HS512],
                         key,
                     })),
                     claims_checker,
@@ -214,7 +228,7 @@ where
         let header = decode_header(token)?;
         // TODO: (optimisation) build & store jwt_validation in key data, to avoid rebuilding it for each check
         let val_key = self.key_source.get_key(header).await?;
-        let jwt_validation = &self.validation.to_jwt_validation(val_key.alg.clone());
+        let jwt_validation = &self.validation.to_jwt_validation(val_key.algs.clone());
         let token_data = decode::<C>(token, &val_key.key, jwt_validation)?;
 
         if let Some(ref checker) = self.claims_checker {
diff --git a/jwt-authorizer/src/jwks/mod.rs b/jwt-authorizer/src/jwks/mod.rs
index 4d07f06..f745df6 100644
--- a/jwt-authorizer/src/jwks/mod.rs
+++ b/jwt-authorizer/src/jwks/mod.rs
@@ -1,6 +1,9 @@
 use std::{str::FromStr, sync::Arc};
 
-use jsonwebtoken::{jwk::Jwk, Algorithm, DecodingKey, Header};
+use jsonwebtoken::{
+    jwk::{AlgorithmParameters, Jwk},
+    Algorithm, DecodingKey, Header,
+};
 
 use crate::error::AuthError;
 
@@ -21,15 +24,40 @@ pub enum KeySource {
 #[derive(Clone)]
 pub struct KeyData {
     pub kid: Option<String>,
-    pub alg: Vec<Algorithm>,
+    /// valid algorithms
+    pub algs: Vec<Algorithm>,
     pub key: DecodingKey,
 }
 
+fn get_valid_algs(key: &Jwk) -> Vec<Algorithm> {
+    if let Some(key_alg) = key.common.key_algorithm {
+        // if alg is not correct => no valid algs => empty array
+        Algorithm::from_str(key_alg.to_string().as_str()).map_or(vec![], |a| vec![a])
+    } else {
+        // guessing valid algs from key structure
+        match key.algorithm {
+            AlgorithmParameters::EllipticCurve(_) => {
+                vec![Algorithm::ES256, Algorithm::ES384]
+            }
+            AlgorithmParameters::RSA(_) => vec![
+                Algorithm::RS256,
+                Algorithm::RS384,
+                Algorithm::RS512,
+                Algorithm::PS256,
+                Algorithm::PS384,
+                Algorithm::PS512,
+            ],
+            AlgorithmParameters::OctetKey(_) => vec![Algorithm::EdDSA],
+            AlgorithmParameters::OctetKeyPair(_) => vec![Algorithm::HS256, Algorithm::HS384, Algorithm::HS512],
+        }
+    }
+}
+
 impl KeyData {
     pub fn from_jwk(key: &Jwk) -> Result<KeyData, jsonwebtoken::errors::Error> {
         Ok(KeyData {
             kid: key.common.key_id.clone(),
-            alg: vec![Algorithm::from_str(key.common.key_algorithm.unwrap().to_string().as_str())?],
+            algs: get_valid_algs(key),
             key: DecodingKey::from_jwk(key)?,
         })
     }
@@ -55,7 +83,7 @@ impl KeySet {
 
     /// Find the key in the set that matches the given key id, if any.
     pub fn find_alg(&self, alg: &Algorithm) -> Option<&Arc<KeyData>> {
-        self.0.iter().find(|k| k.alg.contains(alg))
+        self.0.iter().find(|k| k.algs.contains(alg))
     }
 
     /// Find first key.