diff --git a/dist/otpauth.d.cts b/dist/otpauth.d.cts
new file mode 100644
index 0000000..7b654f6
--- /dev/null
+++ b/dist/otpauth.d.cts
@@ -0,0 +1,383 @@
+/**
+ * OTP secret key.
+ */
+declare class Secret {
+    /**
+     * Converts a Latin-1 string to a Secret object.
+     * @param {string} str Latin-1 string.
+     * @returns {Secret} Secret object.
+     */
+    static fromLatin1(str: string): Secret;
+    /**
+     * Converts an UTF-8 string to a Secret object.
+     * @param {string} str UTF-8 string.
+     * @returns {Secret} Secret object.
+     */
+    static fromUTF8(str: string): Secret;
+    /**
+     * Converts a base32 string to a Secret object.
+     * @param {string} str Base32 string.
+     * @returns {Secret} Secret object.
+     */
+    static fromBase32(str: string): Secret;
+    /**
+     * Converts a hexadecimal string to a Secret object.
+     * @param {string} str Hexadecimal string.
+     * @returns {Secret} Secret object.
+     */
+    static fromHex(str: string): Secret;
+    /**
+     * Creates a secret key object.
+     * @param {Object} [config] Configuration options.
+     * @param {ArrayBuffer} [config.buffer=randomBytes] Secret key.
+     * @param {number} [config.size=20] Number of random bytes to generate, ignored if 'buffer' is provided.
+     */
+    constructor({ buffer, size }?: {
+        buffer?: ArrayBuffer | undefined;
+        size?: number | undefined;
+    } | undefined);
+    /**
+     * Secret key.
+     * @type {ArrayBuffer}
+     */
+    buffer: ArrayBuffer;
+    /**
+     * Latin-1 string representation of secret key.
+     * @type {string}
+     */
+    get latin1(): string;
+    /**
+     * UTF-8 string representation of secret key.
+     * @type {string}
+     */
+    get utf8(): string;
+    /**
+     * Base32 string representation of secret key.
+     * @type {string}
+     */
+    get base32(): string;
+    /**
+     * Hexadecimal string representation of secret key.
+     * @type {string}
+     */
+    get hex(): string;
+}
+
+/**
+ * HOTP: An HMAC-based One-time Password Algorithm.
+ * @see [RFC 4226](https://tools.ietf.org/html/rfc4226)
+ */
+declare class HOTP {
+    /**
+     * Default configuration.
+     * @type {{
+     *   issuer: string,
+     *   label: string,
+     *   issuerInLabel: boolean,
+     *   algorithm: string,
+     *   digits: number,
+     *   counter: number
+     *   window: number
+     * }}
+     */
+    static get defaults(): {
+        issuer: string;
+        label: string;
+        issuerInLabel: boolean;
+        algorithm: string;
+        digits: number;
+        counter: number;
+        window: number;
+    };
+    /**
+     * Generates an HOTP token.
+     * @param {Object} config Configuration options.
+     * @param {Secret} config.secret Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} [config.digits=6] Token length.
+     * @param {number} [config.counter=0] Counter value.
+     * @returns {string} Token.
+     */
+    static generate({ secret, algorithm, digits, counter, }: {
+        secret: Secret;
+        algorithm?: string | undefined;
+        digits?: number | undefined;
+        counter?: number | undefined;
+    }): string;
+    /**
+     * Validates an HOTP token.
+     * @param {Object} config Configuration options.
+     * @param {string} config.token Token value.
+     * @param {Secret} config.secret Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} config.digits Token length.
+     * @param {number} [config.counter=0] Counter value.
+     * @param {number} [config.window=1] Window of counter values to test.
+     * @returns {number|null} Token delta or null if it is not found in the search window, in which case it should be considered invalid.
+     */
+    static validate({ token, secret, algorithm, digits, counter, window, }: {
+        token: string;
+        secret: Secret;
+        algorithm?: string | undefined;
+        digits: number;
+        counter?: number | undefined;
+        window?: number | undefined;
+    }): number | null;
+    /**
+     * Creates an HOTP object.
+     * @param {Object} [config] Configuration options.
+     * @param {string} [config.issuer=''] Account provider.
+     * @param {string} [config.label='OTPAuth'] Account label.
+     * @param {boolean} [config.issuerInLabel=true] Include issuer prefix in label.
+     * @param {Secret|string} [config.secret=Secret] Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} [config.digits=6] Token length.
+     * @param {number} [config.counter=0] Initial counter value.
+     */
+    constructor({ issuer, label, issuerInLabel, secret, algorithm, digits, counter, }?: {
+        issuer?: string | undefined;
+        label?: string | undefined;
+        issuerInLabel?: boolean | undefined;
+        secret?: string | Secret | undefined;
+        algorithm?: string | undefined;
+        digits?: number | undefined;
+        counter?: number | undefined;
+    } | undefined);
+    /**
+     * Account provider.
+     * @type {string}
+     */
+    issuer: string;
+    /**
+     * Account label.
+     * @type {string}
+     */
+    label: string;
+    /**
+     * Include issuer prefix in label.
+     * @type {boolean}
+     */
+    issuerInLabel: boolean;
+    /**
+     * Secret key.
+     * @type {Secret}
+     */
+    secret: Secret;
+    /**
+     * HMAC hashing algorithm.
+     * @type {string}
+     */
+    algorithm: string;
+    /**
+     * Token length.
+     * @type {number}
+     */
+    digits: number;
+    /**
+     * Initial counter value.
+     * @type {number}
+     */
+    counter: number;
+    /**
+     * Generates an HOTP token.
+     * @param {Object} [config] Configuration options.
+     * @param {number} [config.counter=this.counter++] Counter value.
+     * @returns {string} Token.
+     */
+    generate({ counter }?: {
+        counter?: number | undefined;
+    } | undefined): string;
+    /**
+     * Validates an HOTP token.
+     * @param {Object} config Configuration options.
+     * @param {string} config.token Token value.
+     * @param {number} [config.counter=this.counter] Counter value.
+     * @param {number} [config.window=1] Window of counter values to test.
+     * @returns {number|null} Token delta or null if it is not found in the search window, in which case it should be considered invalid.
+     */
+    validate({ token, counter, window }: {
+        token: string;
+        counter?: number | undefined;
+        window?: number | undefined;
+    }): number | null;
+    /**
+     * Returns a Google Authenticator key URI.
+     * @returns {string} URI.
+     */
+    toString(): string;
+}
+
+/**
+ * TOTP: Time-Based One-Time Password Algorithm.
+ * @see [RFC 6238](https://tools.ietf.org/html/rfc6238)
+ */
+declare class TOTP {
+    /**
+     * Default configuration.
+     * @type {{
+     *   issuer: string,
+     *   label: string,
+     *   issuerInLabel: boolean,
+     *   algorithm: string,
+     *   digits: number,
+     *   period: number
+     *   window: number
+     * }}
+     */
+    static get defaults(): {
+        issuer: string;
+        label: string;
+        issuerInLabel: boolean;
+        algorithm: string;
+        digits: number;
+        period: number;
+        window: number;
+    };
+    /**
+     * Generates a TOTP token.
+     * @param {Object} config Configuration options.
+     * @param {Secret} config.secret Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} [config.digits=6] Token length.
+     * @param {number} [config.period=30] Token time-step duration.
+     * @param {number} [config.timestamp=Date.now] Timestamp value in milliseconds.
+     * @returns {string} Token.
+     */
+    static generate({ secret, algorithm, digits, period, timestamp, }: {
+        secret: Secret;
+        algorithm?: string | undefined;
+        digits?: number | undefined;
+        period?: number | undefined;
+        timestamp?: number | undefined;
+    }): string;
+    /**
+     * Validates a TOTP token.
+     * @param {Object} config Configuration options.
+     * @param {string} config.token Token value.
+     * @param {Secret} config.secret Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} config.digits Token length.
+     * @param {number} [config.period=30] Token time-step duration.
+     * @param {number} [config.timestamp=Date.now] Timestamp value in milliseconds.
+     * @param {number} [config.window=1] Window of counter values to test.
+     * @returns {number|null} Token delta or null if it is not found in the search window, in which case it should be considered invalid.
+     */
+    static validate({ token, secret, algorithm, digits, period, timestamp, window, }: {
+        token: string;
+        secret: Secret;
+        algorithm?: string | undefined;
+        digits: number;
+        period?: number | undefined;
+        timestamp?: number | undefined;
+        window?: number | undefined;
+    }): number | null;
+    /**
+     * Creates a TOTP object.
+     * @param {Object} [config] Configuration options.
+     * @param {string} [config.issuer=''] Account provider.
+     * @param {string} [config.label='OTPAuth'] Account label.
+     * @param {boolean} [config.issuerInLabel=true] Include issuer prefix in label.
+     * @param {Secret|string} [config.secret=Secret] Secret key.
+     * @param {string} [config.algorithm='SHA1'] HMAC hashing algorithm.
+     * @param {number} [config.digits=6] Token length.
+     * @param {number} [config.period=30] Token time-step duration.
+     */
+    constructor({ issuer, label, issuerInLabel, secret, algorithm, digits, period, }?: {
+        issuer?: string | undefined;
+        label?: string | undefined;
+        issuerInLabel?: boolean | undefined;
+        secret?: string | Secret | undefined;
+        algorithm?: string | undefined;
+        digits?: number | undefined;
+        period?: number | undefined;
+    } | undefined);
+    /**
+     * Account provider.
+     * @type {string}
+     */
+    issuer: string;
+    /**
+     * Account label.
+     * @type {string}
+     */
+    label: string;
+    /**
+     * Include issuer prefix in label.
+     * @type {boolean}
+     */
+    issuerInLabel: boolean;
+    /**
+     * Secret key.
+     * @type {Secret}
+     */
+    secret: Secret;
+    /**
+     * HMAC hashing algorithm.
+     * @type {string}
+     */
+    algorithm: string;
+    /**
+     * Token length.
+     * @type {number}
+     */
+    digits: number;
+    /**
+     * Token time-step duration.
+     * @type {number}
+     */
+    period: number;
+    /**
+     * Generates a TOTP token.
+     * @param {Object} [config] Configuration options.
+     * @param {number} [config.timestamp=Date.now] Timestamp value in milliseconds.
+     * @returns {string} Token.
+     */
+    generate({ timestamp }?: {
+        timestamp?: number | undefined;
+    } | undefined): string;
+    /**
+     * Validates a TOTP token.
+     * @param {Object} config Configuration options.
+     * @param {string} config.token Token value.
+     * @param {number} [config.timestamp=Date.now] Timestamp value in milliseconds.
+     * @param {number} [config.window=1] Window of counter values to test.
+     * @returns {number|null} Token delta or null if it is not found in the search window, in which case it should be considered invalid.
+     */
+    validate({ token, timestamp, window }: {
+        token: string;
+        timestamp?: number | undefined;
+        window?: number | undefined;
+    }): number | null;
+    /**
+     * Returns a Google Authenticator key URI.
+     * @returns {string} URI.
+     */
+    toString(): string;
+}
+
+/**
+ * HOTP/TOTP object/string conversion.
+ * @see [Key URI Format](https://github.com/google/google-authenticator/wiki/Key-Uri-Format)
+ */
+declare class URI {
+    /**
+     * Parses a Google Authenticator key URI and returns an HOTP/TOTP object.
+     * @param {string} uri Google Authenticator Key URI.
+     * @returns {HOTP|TOTP} HOTP/TOTP object.
+     */
+    static parse(uri: string): HOTP | TOTP;
+    /**
+     * Converts an HOTP/TOTP object to a Google Authenticator key URI.
+     * @param {HOTP|TOTP} otp HOTP/TOTP object.
+     * @returns {string} Google Authenticator Key URI.
+     */
+    static stringify(otp: HOTP | TOTP): string;
+}
+
+/**
+ * Library version.
+ * @type {string}
+ */
+declare const version: string;
+
+export { HOTP, Secret, TOTP, URI, version };
diff --git a/package.json b/package.json
index 215bfb8..b1519b9 100644
--- a/package.json
+++ b/package.json
@@ -36,7 +36,10 @@
   "browser": "./dist/otpauth.esm.js",
   "exports": {
     ".": {
-      "types": "./dist/otpauth.d.ts",
+      "types": {
+        "import": "./dist/otpauth.d.ts",
+        "require": "./dist/otpauth.d.cts"
+      },
       "bun": "./dist/otpauth.esm.js",
       "deno": "./dist/otpauth.esm.js",
       "node": {
@@ -46,7 +49,10 @@
       "default": "./dist/otpauth.esm.js"
     },
     "./dist/*": {
-      "types": "./dist/otpauth.d.ts",
+      "types": {
+        "import": "./dist/otpauth.d.ts",
+        "require": "./dist/otpauth.d.cts"
+      },
       "default": "./dist/*"
     }
   },
diff --git a/rollup.config.mjs b/rollup.config.mjs
index 6d3ddb4..026536b 100644
--- a/rollup.config.mjs
+++ b/rollup.config.mjs
@@ -120,7 +120,10 @@ export default async () => {
     },
     {
       input: "./types/index.d.ts",
-      output: [{ file: "./dist/otpauth.d.ts", format: "es" }],
+      output: [
+        { file: "./dist/otpauth.d.ts", format: "es" },
+        { file: "./dist/otpauth.d.cts", format: "cjs" },
+      ],
       plugins: [dts()],
     },
   ];