diff --git a/.circleci/config.yml b/.circleci/config.yml
index dddc4f96..33790632 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -2,7 +2,7 @@ version: 2
 jobs:
   build:
     docker:
-      - image: circleci/node:10-browsers
+      - image: circleci/node:12-browsers
     environment:
       LANG: en_US.UTF-8
     steps:
diff --git a/lib/config.js b/lib/config.js
index db3823d3..8f0d8070 100644
--- a/lib/config.js
+++ b/lib/config.js
@@ -126,7 +126,11 @@ const paramsSchema = Joi.object({
   idpLogout: Joi.boolean()
     .optional()
     .default((parent) => parent.auth0Logout || false),
-  idTokenSigningAlg: Joi.string().not('none').optional().default('RS256'),
+  idTokenSigningAlg: Joi.string()
+    .insensitive()
+    .not('none')
+    .optional()
+    .default('RS256'),
   issuerBaseURL: Joi.string().uri().required(),
   legacySameSiteCookie: Joi.boolean().optional().default(true),
   authRequired: Joi.boolean().optional().default(true),
diff --git a/test/config.tests.js b/test/config.tests.js
index 3a3b5859..72904fca 100644
--- a/test/config.tests.js
+++ b/test/config.tests.js
@@ -371,15 +371,15 @@ describe('get config', () => {
   });
 
   it('should not allow "none" for idTokenSigningAlg', () => {
-    const config = {
-      ...defaultConfig,
-      idTokenSigningAlg: 'none',
-    };
-    assert.throws(
-      () => getConfig(config),
-      TypeError,
-      '"idTokenSigningAlg" contains an invalid value'
-    );
+    let config = (idTokenSigningAlg) =>
+      getConfig({
+        ...defaultConfig,
+        idTokenSigningAlg,
+      });
+    let expected = '"idTokenSigningAlg" contains an invalid value';
+    assert.throws(() => config('none'), TypeError, expected);
+    assert.throws(() => config('NONE'), TypeError, expected);
+    assert.throws(() => config('noNE'), TypeError, expected);
   });
 
   it('should require clientSecret for ID tokens with HMAC based algorithms', () => {