diff --git a/types/year-days/index.d.ts b/types/year-days/index.d.ts
new file mode 100644
index 0000000000..e951377bed
--- /dev/null
+++ b/types/year-days/index.d.ts
@@ -0,0 +1,8 @@
+// Type definitions for year-days 2.0
+// Project: https://github.com/sindresorhus/year-days#readme
+// Definitions by: BendingBender <https://github.com/BendingBender>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+export = yearDays;
+
+declare function yearDays(year?: number | Date): number;
diff --git a/types/year-days/tsconfig.json b/types/year-days/tsconfig.json
new file mode 100644
index 0000000000..094bd81f6d
--- /dev/null
+++ b/types/year-days/tsconfig.json
@@ -0,0 +1,23 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "year-days-tests.ts"
+    ]
+}
diff --git a/types/year-days/tslint.json b/types/year-days/tslint.json
new file mode 100644
index 0000000000..3db14f85ea
--- /dev/null
+++ b/types/year-days/tslint.json
@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }
diff --git a/types/year-days/year-days-tests.ts b/types/year-days/year-days-tests.ts
new file mode 100644
index 0000000000..e3d67ad831
--- /dev/null
+++ b/types/year-days/year-days-tests.ts
@@ -0,0 +1,8 @@
+import yearDays = require('year-days');
+
+// $ExpectType number
+yearDays();
+// $ExpectType number
+yearDays(2016);
+// $ExpectType number
+yearDays(new Date());