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snippets/js/s/count-occurrences.md

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+---
+title: Count occurrences
+type: snippet
+language: javascript
+tags: [array]
+cover: dark-leaves-4
+dateModified: 2020-10-18T23:04:45+03:00
+---
+
+Counts the occurrences of a value in an array.
+
+- Use `Array.prototype.reduce()` to increment a counter each time the specific value is encountered inside the array.
+
+```js
+const countOccurrences = (arr, val) =>
+  arr.reduce((a, v) => (v === val ? a + 1 : a), 0);
+```
+
+```js
+countOccurrences([1, 1, 2, 1, 2, 3], 1); // 3
+```