diff --git a/package.json b/package.json
index 26ab06f..8a82401 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "description": "Lat/lon normalization cause...**sigh**",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1",
+    "test": "node test.js",
     "semantic-release": "semantic-release pre && npm publish && semantic-release post"
   },
   "repository": {
diff --git a/test.js b/test.js
new file mode 100644
index 0000000..5911005
--- /dev/null
+++ b/test.js
@@ -0,0 +1,30 @@
+const assert = require('assert')
+const ll = require('./')
+
+const lat = 38.13234
+const lng = 70.01232
+const latlng = {lat, lng}
+const point = {x: lng, y: lat}
+const coordinates = [lng, lat]
+const str = `${lng},${lat}`
+
+const pairs = [
+  // normalization
+  [latlng, ll(latlng)],
+  [latlng, ll(point)],
+  [latlng, ll(coordinates)],
+  [latlng, ll(str)],
+
+  // convert to type, normalizes to `latlng` first in each function
+  [ll.toCoordinates(latlng), coordinates],
+  [ll.toPoint(latlng), point],
+  [ll.toString(latlng), str],
+
+  // if the type is known, use the specific convert function directly
+  [latlng, ll.fromLatlng(latlng)],
+  [latlng, ll.fromCoordinates(coordinates)],
+  [latlng, ll.fromPoint(point)],
+  [latlng, ll.fromString(str)]
+]
+
+pairs.forEach((pair) => assert.deepEqual(pair[0], pair[1]))