diff --git a/simple-jwt/src/main/java/com/onixbyte/jwt/constant/HeaderClaims.java b/simple-jwt/src/main/java/com/onixbyte/jwt/constant/HeaderClaims.java
new file mode 100644
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+++ b/simple-jwt/src/main/java/com/onixbyte/jwt/constant/HeaderClaims.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2024-2025 OnixByte.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.onixbyte.jwt.constant;
+
+public final class HeaderClaims {
+
+    /**
+     * Private constructor to prevent instantiation of this utility class.
+     */
+    private HeaderClaims() {
+    }
+
+    /**
+     * The algorithm used to sign a JWT.
+     */
+    public static final String ALGORITHM = "alg";
+
+    /**
+     * The content type of the JWT.
+     */
+    public static final String CONTENT_TYPE = "cty";
+
+    /**
+     * The media type of the JWT.
+     */
+    public static final String TYPE = "typ";
+
+    /**
+     * The key ID of a JWT used to specify the key for signature validation.
+     */
+    public static final String KEY_ID = "kid";
+
+}
diff --git a/simple-jwt/src/main/java/com/onixbyte/jwt/constant/RegisteredClaims.java b/simple-jwt/src/main/java/com/onixbyte/jwt/constant/RegisteredClaims.java
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+++ b/simple-jwt/src/main/java/com/onixbyte/jwt/constant/RegisteredClaims.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2024-2025 OnixByte.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.onixbyte.jwt.constant;
+
+import java.util.List;
+
+/**
+ *
+ */
+public final class RegisteredClaims {
+
+    /**
+     * Private constructor to prevent instantiation of this utility class.
+     */
+    private RegisteredClaims() {
+    }
+
+    /**
+     * The "iss" (issuer) claim identifies the principal that issued the JWT.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1">Section 4.1.1</a>
+     */
+    public static final String ISSUER = "iss";
+
+    /**
+     * The "sub" (subject) claim identifies the principal that is the subject of the JWT.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.2">Section 4.1.2</a>
+     */
+    public static final String SUBJECT = "sub";
+
+    /**
+     * The "aud" (audience) claim identifies the recipients that the JWT is intended for.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.3">Section 4.1.3</a>
+     */
+    public static final String AUDIENCE = "aud";
+
+    /**
+     * The "exp" (expiration time) claim identifies the expiration time on or after which the JWT MUST NOT be
+     * accepted for processing.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4">Section 4.1.4</a>
+     */
+    public static final String EXPIRES_AT = "exp";
+
+    /**
+     * The "nbf" (not before) claim identifies the time before which the JWT MUST NOT be accepted for processing.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.5">Section 4.1.5</a>
+     */
+    public static final String NOT_BEFORE = "nbf";
+
+    /**
+     * The "iat" (issued at) claim identifies the time at which the JWT was issued.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.6">Section 4.1.6</a>
+     */
+    public static final String ISSUED_AT = "iat";
+
+    /**
+     * The "jti" (JWT ID) claim provides a unique identifier for the JWT.
+     * Refer RFC 7529 <a href="https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7">Section 4.1.7</a>
+     */
+    public static final String TOKEN_ID = "jti";
+
+    public static final List<String> VALUES = List.of(ISSUER, SUBJECT, AUDIENCE, EXPIRES_AT, NOT_BEFORE, ISSUED_AT, TOKEN_ID);
+
+}