diff --git a/lib/keyUtils.js b/lib/keyUtils.js
index 201070d3..dc87cb1f 100644
--- a/lib/keyUtils.js
+++ b/lib/keyUtils.js
@@ -114,7 +114,7 @@ const algToJWKAlg = {
 	"RSASSA-PKCS1-v1_5_w_SHA256": "RS256",
 	"RSASSA-PKCS1-v1_5_w_SHA384": "RS384",
 	"RSASSA-PKCS1-v1_5_w_SHA512": "RS512",
-	"RSASSA-PKCS1-v1_5_w_SHA1": "RS256",
+	"RSASSA-PKCS1-v1_5_w_SHA1": "RS1",
 	/*
 	PS256-512 is untested 
 	"RSASSA-PSS_w_SHA-256": "PS256",