diff --git a/snippets/intersectionBy.md b/snippets/intersectionBy.md
new file mode 100644
index 000000000..3f28a78be
--- /dev/null
+++ b/snippets/intersectionBy.md
@@ -0,0 +1,16 @@
+### intersectionBy
+
+Returns a list of elements that exist in both arrays, after applying the provided function to each array element of both.
+
+Create a `Set` by applying `fn` to all elements in `b`, then use `Array.filter()` on `a` to only keep elements, which produce values contained in `b` when `fn` is applied to them.
+
+```js
+const intersectionBy = (a, b, fn) => {
+  const s = new Set(b.map(x => fn(x)));
+  return a.filter(x => s.has(fn(x)));
+};
+```
+
+```js
+intersectionBy([2.1, 1.2], [2.3, 3.4], Math.floor); // [2.1]
+```
diff --git a/snippets/intersectionWith.md b/snippets/intersectionWith.md
new file mode 100644
index 000000000..ae5483c47
--- /dev/null
+++ b/snippets/intersectionWith.md
@@ -0,0 +1,14 @@
+### intersectionWith
+
+Returns a list of elements that exist in both arrays, using a provided comparator function.
+
+Use `Array.filter()` and `Array.findIndex()` in combination with the provided comparator to determine intersecting values.
+
+```js
+const intersectionWith = (a, b, comp) =>
+  a.filter(x => b.findIndex(y => comp(x, y)) !== -1);
+```
+
+```js
+intersectionWith([1, 1.2, 1.5, 3, 0], [1.9, 3, 0, 3.9], (a, b) => Math.round(a) === Math.round(b)); // [1.5, 3, 0]
+```
diff --git a/tag_database b/tag_database
index a4eac6748..78f14816c 100644
--- a/tag_database
+++ b/tag_database
@@ -91,6 +91,8 @@ initializeArrayWithRangeRight:array,math
 initializeArrayWithValues:array,math
 inRange:math
 intersection:array,math
+intersectionBy:array,function
+intersectionWith:array,function
 invertKeyValues:object,function
 is:type,array,regexp
 isAbsoluteURL:string,utility,browser,url