diff --git a/test/id.test.js b/test/id.test.js
new file mode 100644
index 0000000..1d5a7f1
--- /dev/null
+++ b/test/id.test.js
@@ -0,0 +1,54 @@
+const test = require('ava');
+const BemEntityName = require('@bem/entity-name');
+
+const BemCell = require('../index');
+
+test('should provide `id` field', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' }),
+        layer: 'desktop',
+        tech: 'css'
+    });
+
+    t.is(cell.id, 'block@desktop.css');
+});
+
+test('should provide `id` field for cell with entity `field` only', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' })
+    });
+
+    t.is(cell.id, 'block');
+});
+
+test('should provide `id` field for cell with `tech` field', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' }),
+        tech: 'css'
+    });
+
+    t.is(cell.id, 'block.css');
+});
+
+test('should provide `id` field for cell with `layer` field', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' }),
+        layer: 'desktop',
+    });
+
+    t.is(cell.id, 'block@desktop');
+});
+
+test('should cache `id` field', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' }),
+        layer: 'desktop',
+        tech: 'css'
+    });
+    const id = cell.id;
+
+    cell._tech = 'js';
+    cell._layer = 'common';
+
+    t.is(cell.id, id);
+});