diff --git a/pkg/client/rp/relaying_party.go b/pkg/client/rp/relaying_party.go
index a72fa21..669a910 100644
--- a/pkg/client/rp/relaying_party.go
+++ b/pkg/client/rp/relaying_party.go
@@ -289,7 +289,7 @@ func AuthURLHandler(stateFn func() string, rp RelyingParty) http.HandlerFunc {
 
 //GenerateAndStoreCodeChallenge generates a PKCE code challenge and stores its verifier into a secure cookie
 func GenerateAndStoreCodeChallenge(w http.ResponseWriter, rp RelyingParty) (string, error) {
-	codeVerifier := base64.URLEncoding.EncodeToString([]byte(uuid.New().String()))
+	codeVerifier := base64.RawURLEncoding.EncodeToString([]byte(uuid.New().String()))
 	if err := rp.CookieHandler().SetCookie(w, pkceCode, codeVerifier); err != nil {
 		return "", err
 	}