diff --git a/cli/tsc/dts/lib.deno.ns.d.ts b/cli/tsc/dts/lib.deno.ns.d.ts
index 80c9851840..cc73efbf90 100644
--- a/cli/tsc/dts/lib.deno.ns.d.ts
+++ b/cli/tsc/dts/lib.deno.ns.d.ts
@@ -6281,13 +6281,7 @@ declare namespace Deno {
    *
    * @category HTTP Server
    */
-  export interface ServeTlsOptions extends ServeOptions {
-    /** Server private key in PEM format */
-    cert: string;
-
-    /** Cert chain in PEM format */
-    key: string;
-  }
+  export type ServeTlsOptions = ServeOptions & TlsCertifiedKeyOptions;
 
   /**
    * @category HTTP Server
diff --git a/cli/tsc/dts/lib.deno.unstable.d.ts b/cli/tsc/dts/lib.deno.unstable.d.ts
index 056d8e6099..ae3f60d283 100644
--- a/cli/tsc/dts/lib.deno.unstable.d.ts
+++ b/cli/tsc/dts/lib.deno.unstable.d.ts
@@ -882,10 +882,6 @@ declare namespace Deno {
     caCerts?: string[];
     /** A HTTP proxy to use for new connections. */
     proxy?: Proxy;
-    /** Cert chain in PEM format. */
-    cert?: string;
-    /** Server private key in PEM format. */
-    key?: string;
     /** Sets the maximum numer of idle connections per host allowed in the pool. */
     poolMaxIdlePerHost?: number;
     /** Set an optional timeout for idle sockets being kept-alive.
@@ -962,6 +958,27 @@ declare namespace Deno {
     options: CreateHttpClientOptions,
   ): HttpClient;
 
+  /** **UNSTABLE**: New API, yet to be vetted.
+   *
+   * Create a custom HttpClient to use with {@linkcode fetch}. This is an
+   * extension of the web platform Fetch API which allows Deno to use custom
+   * TLS certificates and connect via a proxy while using `fetch()`.
+   *
+   * @example ```ts
+   * const caCert = await Deno.readTextFile("./ca.pem");
+   * // Load a client key and certificate that we'll use to connect
+   * const key = await Deno.readTextFile("./key.key");
+   * const cert = await Deno.readTextFile("./cert.crt");
+   * const client = Deno.createHttpClient({ caCerts: [ caCert ], key, cert });
+   * const response = await fetch("https://myserver.com", { client });
+   * ```
+   *
+   * @category Fetch API
+   */
+  export function createHttpClient(
+    options: CreateHttpClientOptions & TlsCertifiedKeyOptions,
+  ): HttpClient;
+
   /** **UNSTABLE**: New API, yet to be vetted.
    *
    * Represents membership of a IPv4 multicast group.
diff --git a/ext/fetch/22_http_client.js b/ext/fetch/22_http_client.js
index e1389bbe1f..061a3dda89 100644
--- a/ext/fetch/22_http_client.js
+++ b/ext/fetch/22_http_client.js
@@ -25,12 +25,7 @@ const { ObjectDefineProperty } = primordials;
  */
 function createHttpClient(options) {
   options.caCerts ??= [];
-  const keyPair = loadTlsKeyPair(
-    options.cert,
-    undefined,
-    options.key,
-    undefined,
-  );
+  const keyPair = loadTlsKeyPair("Deno.createHttpClient", options);
   return new HttpClient(
     op_fetch_custom_client(
       options,
diff --git a/ext/net/02_tls.js b/ext/net/02_tls.js
index 8d43e8604f..003c5336a7 100644
--- a/ext/net/02_tls.js
+++ b/ext/net/02_tls.js
@@ -51,54 +51,46 @@ async function connectTls({
   port,
   hostname = "127.0.0.1",
   transport = "tcp",
-  certFile = undefined,
   caCerts = [],
-  certChain = undefined,
-  privateKey = undefined,
-  cert = undefined,
-  key = undefined,
   alpnProtocols = undefined,
+  keyFormat = undefined,
+  cert = undefined,
+  certFile = undefined,
+  certChain = undefined,
+  key = undefined,
+  keyFile = undefined,
+  privateKey = undefined,
 }) {
-  if (certFile !== undefined) {
-    internals.warnOnDeprecatedApi(
-      "Deno.ConnectTlsOptions.certFile",
-      new Error().stack,
-      "Pass the cert file contents to the `Deno.ConnectTlsOptions.cert` option instead.",
-    );
-  }
-  if (certChain !== undefined) {
-    internals.warnOnDeprecatedApi(
-      "Deno.ConnectTlsOptions.certChain",
-      new Error().stack,
-      "Use the `Deno.ConnectTlsOptions.cert` option instead.",
-    );
-  }
-  if (privateKey !== undefined) {
-    internals.warnOnDeprecatedApi(
-      "Deno.ConnectTlsOptions.privateKey",
-      new Error().stack,
-      "Use the `Deno.ConnectTlsOptions.key` option instead.",
-    );
-  }
   if (transport !== "tcp") {
     throw new TypeError(`Unsupported transport: '${transport}'`);
   }
-  if (certChain !== undefined && cert !== undefined) {
-    throw new TypeError(
-      "Cannot specify both `certChain` and `cert`",
+  let deprecatedCertFile = undefined;
+
+  // Deno.connectTls has an irregular option where you can just pass `certFile` and
+  // not `keyFile`. In this case it's used for `caCerts` rather than the client key.
+  if (certFile !== undefined && keyFile === undefined) {
+    internals.warnOnDeprecatedApi(
+      "Deno.ConnectTlsOptions.certFile",
+      new Error().stack,
+      "Pass the cert file's contents to the `Deno.ConnectTlsOptions.caCerts` option instead.",
     );
+
+    deprecatedCertFile = certFile;
+    certFile = undefined;
   }
-  if (privateKey !== undefined && key !== undefined) {
-    throw new TypeError(
-      "Cannot specify both `privateKey` and `key`",
-    );
-  }
-  cert ??= certChain;
-  key ??= privateKey;
-  const keyPair = loadTlsKeyPair(cert, undefined, key, undefined);
+
+  const keyPair = loadTlsKeyPair("Deno.connectTls", {
+    keyFormat,
+    cert,
+    certFile,
+    certChain,
+    key,
+    keyFile,
+    privateKey,
+  });
   const { 0: rid, 1: localAddr, 2: remoteAddr } = await op_net_connect_tls(
     { hostname, port },
-    { certFile, caCerts, cert, key, alpnProtocols },
+    { certFile: deprecatedCertFile, caCerts, alpnProtocols },
     keyPair,
   );
   localAddr.transport = "tcp";
@@ -137,29 +129,96 @@ class TlsListener extends Listener {
   }
 }
 
+/**
+ * Returns true if this object has the shape of one of the certified key material
+ * interfaces.
+ */
 function hasTlsKeyPairOptions(options) {
   return (ReflectHas(options, "cert") || ReflectHas(options, "key") ||
     ReflectHas(options, "certFile") ||
-    ReflectHas(options, "keyFile"));
+    ReflectHas(options, "keyFile") || ReflectHas(options, "privateKey") ||
+    ReflectHas(options, "certChain"));
 }
 
-function loadTlsKeyPair(
+/**
+ * Loads a TLS keypair from one of the various options. If no key material is provided,
+ * returns a special Null keypair.
+ */
+function loadTlsKeyPair(api, {
+  keyFormat,
   cert,
   certFile,
+  certChain,
   key,
   keyFile,
-) {
-  if ((certFile !== undefined) ^ (keyFile !== undefined)) {
-    throw new TypeError(
-      "If certFile is specified, keyFile must also be specified",
-    );
-  }
-  if ((cert !== undefined) ^ (key !== undefined)) {
-    throw new TypeError("If cert is specified, key must also be specified");
+  privateKey,
+}) {
+  // Check for "pem" format
+  if (keyFormat !== undefined && keyFormat !== "pem") {
+    throw new TypeError('If `keyFormat` is specified, it must be "pem"');
   }
 
+  function exclusive(a1, a1v, a2, a2v) {
+    if (a1v !== undefined && a2v !== undefined) {
+      throw new TypeError(
+        `Cannot specify both \`${a1}\` and \`${a2}\` for \`${api}\`.`,
+      );
+    }
+  }
+
+  // Ensure that only one pair is valid
+  exclusive("certChain", certChain, "cert", cert);
+  exclusive("certChain", certChain, "certFile", certFile);
+  exclusive("key", key, "keyFile", keyFile);
+  exclusive("key", key, "privateKey", privateKey);
+
+  function both(a1, a1v, a2, a2v) {
+    if (a1v !== undefined && a2v === undefined) {
+      throw new TypeError(
+        `If \`${a1}\` is specified, \`${a2}\` must be specified as well for \`${api}\`.`,
+      );
+    }
+    if (a1v === undefined && a2v !== undefined) {
+      throw new TypeError(
+        `If \`${a2}\` is specified, \`${a1}\` must be specified as well for \`${api}\`.`,
+      );
+    }
+  }
+
+  // Pick one pair of cert/key, certFile/keyFile or certChain/privateKey
+  both("cert", cert, "key", key);
+  both("certFile", certFile, "keyFile", keyFile);
+  both("certChain", certChain, "privateKey", privateKey);
+
   if (certFile !== undefined) {
-    return op_tls_key_static_from_file("Deno.listenTls", certFile, keyFile);
+    internals.warnOnDeprecatedApi(
+      "Deno.TlsCertifiedKeyOptions.keyFile",
+      new Error().stack,
+      "Pass the key file's contents to the `Deno.TlsCertifiedKeyPem.key` option instead.",
+    );
+    internals.warnOnDeprecatedApi(
+      "Deno.TlsCertifiedKeyOptions.certFile",
+      new Error().stack,
+      "Pass the cert file's contents to the `Deno.TlsCertifiedKeyPem.cert` option instead.",
+    );
+    return op_tls_key_static_from_file(api, certFile, keyFile);
+  } else if (certChain !== undefined) {
+    if (api !== "Deno.connectTls") {
+      throw new TypeError(
+        `Invalid options 'certChain' and 'privateKey' for ${api}`,
+      );
+    }
+    internals.warnOnDeprecatedApi(
+      "Deno.TlsCertifiedKeyOptions.privateKey",
+      new Error().stack,
+      "Use the `Deno.TlsCertifiedKeyPem.key` option instead.",
+    );
+    internals.warnOnDeprecatedApi(
+      "Deno.TlsCertifiedKeyOptions.certChain",
+      new Error().stack,
+      "Use the `Deno.TlsCertifiedKeyPem.cert` option instead.",
+    );
+    return op_tls_key_static(certChain, privateKey);
   } else if (cert !== undefined) {
     return op_tls_key_static(cert, key);
   } else {
@@ -169,10 +228,6 @@ function loadTlsKeyPair(
 
 function listenTls({
   port,
-  cert,
-  certFile,
-  key,
-  keyFile,
   hostname = "0.0.0.0",
   transport = "tcp",
   alpnProtocols = undefined,
@@ -181,22 +236,11 @@ function listenTls({
   if (transport !== "tcp") {
     throw new TypeError(`Unsupported transport: '${transport}'`);
   }
-  if (keyFile !== undefined) {
-    internals.warnOnDeprecatedApi(
-      "Deno.ListenTlsOptions.keyFile",
-      new Error().stack,
-      "Pass the key file contents to the `Deno.ListenTlsOptions.key` option instead.",
-    );
-  }
-  if (certFile !== undefined) {
-    internals.warnOnDeprecatedApi(
-      "Deno.ListenTlsOptions.certFile",
-      new Error().stack,
-      "Pass the cert file contents to the `Deno.ListenTlsOptions.cert` option instead.",
-    );
-  }
 
-  const keyPair = loadTlsKeyPair(cert, certFile, key, keyFile);
+  if (!hasTlsKeyPairOptions(arguments[0])) {
+    throw new TypeError("A key and certificate are required for `listenTls`");
+  }
+  const keyPair = loadTlsKeyPair("Deno.listenTls", arguments[0]);
   const { 0: rid, 1: localAddr } = op_net_listen_tls(
     { hostname, port: Number(port) },
     { alpnProtocols, reusePort },
diff --git a/ext/net/lib.deno_net.d.ts b/ext/net/lib.deno_net.d.ts
index 597b3d3483..4b88b154aa 100644
--- a/ext/net/lib.deno_net.d.ts
+++ b/ext/net/lib.deno_net.d.ts
@@ -197,12 +197,50 @@ declare namespace Deno {
     options: UnixListenOptions & { transport: "unix" },
   ): UnixListener;
 
-  /** @category Network */
-  export interface ListenTlsOptions extends TcpListenOptions {
-    /** Server private key in PEM format */
-    key?: string;
-    /** Cert chain in PEM format */
-    cert?: string;
+  /** Provides TLS certified keys, ie: a key that has been certified by a trusted certificate authority.
+   * A certified key generally consists of a private key and certificate part.
+   *
+   * @category Network
+   */
+  export type TlsCertifiedKeyOptions =
+    | TlsCertifiedKeyPem
+    | TlsCertifiedKeyFromFile
+    | TlsCertifiedKeyConnectTls;
+
+  /**
+   * Provides certified key material from strings. The key material is provided in
+   * `PEM`-format (Privacy Enhanced Mail, https://www.rfc-editor.org/rfc/rfc1422) which can be identified by having
+   * `-----BEGIN-----` and `-----END-----` markers at the beginning and end of the strings. This type of key is not compatible
+   * with `DER`-format keys which are binary.
+   *
+   * Deno supports RSA, EC, and PKCS8-format keys.
+   *
+   * ```ts
+   * const key = {
+   *  key: "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----\n",
+   *  cert: "-----BEGIN CERTIFICATE-----\n...\n-----END CERTIFICATE-----\n" }
+   * };
+   * ```
+   *
+   * @category Network
+   */
+  export interface TlsCertifiedKeyPem {
+    /** The format of this key material, which must be PEM. */
+    keyFormat?: "pem";
+    /** Private key in `PEM` format. RSA, EC, and PKCS8-format keys are supported. */
+    key: string;
+    /** Certificate chain in `PEM` format. */
+    cert: string;
+  }
+
+  /**
+   * @deprecated This will be removed in Deno 2.0. See the
+   * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
+   * for migration instructions.
+   *
+   * @category Network
+   */
+  export interface TlsCertifiedKeyFromFile {
     /** Path to a file containing a PEM formatted CA certificate. Requires
      * `--allow-read`.
      *
@@ -211,16 +249,45 @@ declare namespace Deno {
      * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
      * for migration instructions.
      */
-    certFile?: string;
-    /** Server private key file. Requires `--allow-read`.
+    certFile: string;
+    /** Path to a file containing a private key file. Requires `--allow-read`.
      *
      * @tags allow-read
      * @deprecated This will be removed in Deno 2.0. See the
      * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
      * for migration instructions.
      */
-    keyFile?: string;
+    keyFile: string;
+  }
 
+  /**
+   * @deprecated This will be removed in Deno 2.0. See the
+   * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
+   * for migration instructions.
+   *
+   * @category Network
+   */
+  export interface TlsCertifiedKeyConnectTls {
+    /**
+     * Certificate chain in `PEM` format.
+     *
+     * @deprecated This will be removed in Deno 2.0. See the
+     * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
+     * for migration instructions.
+     */
+    certChain: string;
+    /**
+     * Private key in `PEM` format. RSA, EC, and PKCS8-format keys are supported.
+     *
+     * @deprecated This will be removed in Deno 2.0. See the
+     * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
+     * for migration instructions.
+     */
+    privateKey: string;
+  }
+
+  /** @category Network */
+  export interface ListenTlsOptions extends TcpListenOptions {
     transport?: "tcp";
 
     /** Application-Layer Protocol Negotiation (ALPN) protocols to announce to
@@ -246,7 +313,9 @@ declare namespace Deno {
    * @tags allow-net
    * @category Network
    */
-  export function listenTls(options: ListenTlsOptions): TlsListener;
+  export function listenTls(
+    options: ListenTlsOptions & TlsCertifiedKeyOptions,
+  ): TlsListener;
 
   /** @category Network */
   export interface ConnectOptions {
@@ -343,9 +412,11 @@ declare namespace Deno {
      *
      * @default {"127.0.0.1"} */
     hostname?: string;
-    /**
-     * Server certificate file.
+    /** Path to a file containing a PEM formatted list of root certificates that will
+     * be used in addition to the default root certificates to verify the peer's certificate. Requires
+     * `--allow-read`.
      *
+     * @tags allow-read
      * @deprecated This will be removed in Deno 2.0. See the
      * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
      * for migration instructions.
@@ -361,26 +432,6 @@ declare namespace Deno {
      * TLS handshake.
      */
     alpnProtocols?: string[];
-    /**
-     * PEM formatted client certificate chain.
-     *
-     * @deprecated This will be removed in Deno 2.0. See the
-     * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
-     * for migration instructions.
-     */
-    certChain?: string;
-    /**
-     * PEM formatted (RSA or PKCS8) private key of client certificate.
-     *
-     * @deprecated This will be removed in Deno 2.0. See the
-     * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
-     * for migration instructions.
-     */
-    privateKey?: string;
-    /** Server private key in PEM format. */
-    key?: string;
-    /** Cert chain in PEM format. */
-    cert?: string;
   }
 
   /** Establishes a secure connection over TLS (transport layer security) using
@@ -403,6 +454,30 @@ declare namespace Deno {
    */
   export function connectTls(options: ConnectTlsOptions): Promise<TlsConn>;
 
+  /** Establishes a secure connection over TLS (transport layer security) using
+   * an optional cert file, client certificate, hostname (default is "127.0.0.1") and
+   * port.  The cert file is optional and if not included Mozilla's root certificates will
+   * be used (see also https://github.com/ctz/webpki-roots for specifics)
+   *
+   * ```ts
+   * const caCert = await Deno.readTextFile("./certs/my_custom_root_CA.pem");
+   * const key = "----BEGIN PRIVATE KEY----...";
+   * const cert = "----BEGIN CERTIFICATE----...";
+   * const conn1 = await Deno.connectTls({ port: 80, key, cert });
+   * const conn2 = await Deno.connectTls({ caCerts: [caCert], hostname: "192.0.2.1", port: 80, key, cert });
+   * const conn3 = await Deno.connectTls({ hostname: "[2001:db8::1]", port: 80, key, cert });
+   * const conn4 = await Deno.connectTls({ caCerts: [caCert], hostname: "golang.org", port: 80, key, cert });
+   * ```
+   *
+   * Requires `allow-net` permission.
+   *
+   * @tags allow-net
+   * @category Network
+   */
+  export function connectTls(
+    options: ConnectTlsOptions & TlsCertifiedKeyOptions,
+  ): Promise<TlsConn>;
+
   /** @category Network */
   export interface StartTlsOptions {
     /** A literal IP address or host name that can be resolved to an IP address.
diff --git a/tests/unit/tls_test.ts b/tests/unit/tls_test.ts
index 8f0a296c72..5be05b73e3 100644
--- a/tests/unit/tls_test.ts
+++ b/tests/unit/tls_test.ts
@@ -1336,7 +1336,7 @@ Deno.test(
         });
       },
       TypeError,
-      "Cannot specify both `privateKey` and `key`",
+      "Cannot specify both `key` and `privateKey` for `Deno.connectTls`.",
     );
   },
 );