diff --git a/test.ts b/test.ts
index 1f41003f3d6f6e..07e57e35b49407 100755
--- a/test.ts
+++ b/test.ts
@@ -21,6 +21,7 @@ import "./strings/test.ts";
 import "./testing/test.ts";
 import "./textproto/test.ts";
 import "./util/test.ts";
+import "./uuid/test.ts";
 import "./ws/test.ts";
 import "./encoding/test.ts";
 import "./os/test.ts";
diff --git a/uuid/README.md b/uuid/README.md
new file mode 100644
index 00000000000000..513a6ed535f7a5
--- /dev/null
+++ b/uuid/README.md
@@ -0,0 +1,15 @@
+# UUID
+
+Support for version 1, 3, 4, and 5 UUIDs.
+
+## Usage
+
+```ts
+import uuid, { validate } from "https://deno.land/std/uuid/mod.ts";
+
+// Generate a v4 uuid
+const myUUID = uuid();
+
+// Validate a v4 uuid
+const isValid = validate(aString);
+```
diff --git a/uuid/mod.ts b/uuid/mod.ts
new file mode 100644
index 00000000000000..64ca4538575b0d
--- /dev/null
+++ b/uuid/mod.ts
@@ -0,0 +1,26 @@
+// Based on https://github.com/kelektiv/node-uuid
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+export const NIL_UUID = "00000000-0000-0000-0000-000000000000";
+
+export function isNil(val: string): boolean {
+  return val === NIL_UUID;
+}
+
+const NOT_IMPLEMENTED = (): void => {
+  throw new Error("Not implemented");
+};
+
+// TODO Implement
+export const v1 = NOT_IMPLEMENTED;
+// TODO Implement
+export const v3 = NOT_IMPLEMENTED;
+
+import _v4 from "./v4.ts";
+export const v4 = _v4;
+
+// TODO Implement
+export const v5 = NOT_IMPLEMENTED;
+
+export default v4;
+export * from "./v4.ts";
diff --git a/uuid/test.ts b/uuid/test.ts
new file mode 100755
index 00000000000000..72616d3efebe40
--- /dev/null
+++ b/uuid/test.ts
@@ -0,0 +1,13 @@
+#!/usr/bin/env deno run
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { runIfMain } from "../testing/mod.ts";
+
+// Generic Tests
+import "./tests/isNil.ts";
+import "./tests/generate.ts";
+
+// V4 Tests
+import "./tests/v4/validate.ts";
+import "./tests/v4/generate.ts";
+
+runIfMain(import.meta);
diff --git a/uuid/tests/generate.ts b/uuid/tests/generate.ts
new file mode 100644
index 00000000000000..723740641d891f
--- /dev/null
+++ b/uuid/tests/generate.ts
@@ -0,0 +1,32 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { assert, assertEquals } from "../../testing/asserts.ts";
+import { test } from "../../testing/mod.ts";
+import mod, { validate, v4 } from "../mod.ts";
+import { validate as validate4 } from "../v4.ts";
+
+test({
+  name: "[UUID] uuid_v4",
+  fn(): void {
+    const u = mod();
+    assertEquals(typeof u, "string", "returns a string");
+    assert(u !== "", "return string is not empty");
+  }
+});
+
+test({
+  name: "[UUID] uuid_v4_format",
+  fn(): void {
+    for (let i = 0; i < 10000; i++) {
+      const u = mod() as string;
+      assert(validate(u), `${u} is not a valid uuid v4`);
+    }
+  }
+});
+
+test({
+  name: "[UUID] default_is_v4",
+  fn(): void {
+    assertEquals(mod, v4, "default is v4");
+    assertEquals(validate, validate4, "validate is v4");
+  }
+});
diff --git a/uuid/tests/isNil.ts b/uuid/tests/isNil.ts
new file mode 100644
index 00000000000000..29f0feb624d36a
--- /dev/null
+++ b/uuid/tests/isNil.ts
@@ -0,0 +1,16 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { assert } from "../../testing/asserts.ts";
+import { test } from "../../testing/mod.ts";
+// @ts-ignore
+import { NIL_UUID, isNil } from "../mod.ts";
+
+test({
+  name: "[UUID] isNil",
+  fn(): void {
+    const nil = NIL_UUID;
+    const u = "582cbcff-dad6-4f28-888a-e062ae36bafc";
+    assert(isNil(nil));
+    assert(!isNil(u));
+    console.log("");
+  }
+});
diff --git a/uuid/tests/v4/generate.ts b/uuid/tests/v4/generate.ts
new file mode 100644
index 00000000000000..829183d9708d92
--- /dev/null
+++ b/uuid/tests/v4/generate.ts
@@ -0,0 +1,23 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { assert, assertEquals } from "../../../testing/asserts.ts";
+import { test } from "../../../testing/mod.ts";
+import generate, { validate } from "../../v4.ts";
+
+test({
+  name: "[UUID] test_uuid_v4",
+  fn(): void {
+    const u = generate();
+    assertEquals(typeof u, "string", "returns a string");
+    assert(u !== "", "return string is not empty");
+  }
+});
+
+test({
+  name: "[UUID] test_uuid_v4_format",
+  fn(): void {
+    for (let i = 0; i < 10000; i++) {
+      const u = generate() as string;
+      assert(validate(u), `${u} is not a valid uuid v4`);
+    }
+  }
+});
diff --git a/uuid/tests/v4/validate.ts b/uuid/tests/v4/validate.ts
new file mode 100644
index 00000000000000..fdec8383ac3bf8
--- /dev/null
+++ b/uuid/tests/v4/validate.ts
@@ -0,0 +1,17 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { assert } from "../../../testing/asserts.ts";
+import { test } from "../../../testing/mod.ts";
+import generate, { validate } from "../../v4.ts";
+
+test({
+  name: "[UUID] is_valid_uuid_v4",
+  fn(): void {
+    const u = generate();
+    const t = "84fb7824-b951-490e-8afd-0c13228a8282";
+    const n = "84fb7824-b951-490g-8afd-0c13228a8282";
+
+    assert(validate(u), `generated ${u} should be valid`);
+    assert(validate(t), `${t} should be valid`);
+    assert(!validate(n), `${n} should not be valid`);
+  }
+});
diff --git a/uuid/v4.ts b/uuid/v4.ts
new file mode 100644
index 00000000000000..eeb9c4f140396a
--- /dev/null
+++ b/uuid/v4.ts
@@ -0,0 +1,19 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+const UUID_RE = new RegExp(
+  "^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$",
+  "i"
+);
+
+export function validate(id: string): boolean {
+  return UUID_RE.test(id);
+}
+
+export default function generate(): string {
+  return "00000000-0000-4000-8000-000000000000".replace(
+    /[0]/g,
+    (): string =>
+      // random integer from 0 to 15 as a hex digit.
+      (crypto.getRandomValues(new Uint8Array(1))[0] % 16).toString(16)
+  );
+}