diff --git a/types/js-nacl/index.d.ts b/types/js-nacl/index.d.ts
index 94a7cecedf..189d1a7034 100644
--- a/types/js-nacl/index.d.ts
+++ b/types/js-nacl/index.d.ts
@@ -1,4 +1,4 @@
-// Type definitions for js-nacl 1.2
+// Type definitions for js-nacl 1.3
 // Project: https://github.com/tonyg/js-nacl#readme
 // Definitions by: Ethan Frey <https://github.com/ethanfrey>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
@@ -116,6 +116,9 @@ export interface Nacl {
   crypto_box_seed_keypair: (seed: Uint8Array) => BoxKeyPair;
   crypto_box_keypair_from_raw_sk: (seed: Uint8Array) => BoxKeyPair;
 
+  // random
+  random_bytes: (length: number) => Uint8Array;
+
   // TODO: crypto_stream
   // crypto_stream_random_nonce: () => Nonce;
   // crypto_stream: (len: number, nonce: Nonce, key: StreamKey) => Stream;
diff --git a/types/js-nacl/js-nacl-tests.ts b/types/js-nacl/js-nacl-tests.ts
index b3336b11f7..1143357675 100644
--- a/types/js-nacl/js-nacl-tests.ts
+++ b/types/js-nacl/js-nacl-tests.ts
@@ -9,6 +9,7 @@ nacl.instantiate((inst: nacl.Nacl) => {
     demo_box(inst);
     demo_secret_box(inst);
     demo_derived(inst);
+    demo_random(inst);
 });
 
 function demo_hex(inst: nacl.Nacl): void {
@@ -71,3 +72,7 @@ function demo_derived(inst: nacl.Nacl): void {
     inst.crypto_box_seed_keypair(seed); // $ExpectType BoxKeyPair
     inst.crypto_box_keypair_from_raw_sk(seed); // $ExpectType BoxKeyPair
 }
+
+function demo_random(inst: nacl.Nacl): void {
+    inst.random_bytes(32); // $ExpectType Uint8Array
+}