diff --git a/2021/6.js b/2021/6.js
new file mode 100644
index 0000000..040aa70
--- /dev/null
+++ b/2021/6.js
@@ -0,0 +1,15 @@
+function iterate(counts) {
+    return [counts[1], counts[2], counts[3], counts[4], counts[5], counts[6], counts[7] + counts[0], counts[8], counts[0]]
+}
+
+function day6(input, part2) {
+    input = input.split(",").num()
+
+    let counts = Array(9).fill().map((_, i) => input.count(i))
+
+    for (let i = 0; i < (part2 ? 256 : 80); i++) {
+        counts = iterate(counts)
+    }
+
+    return counts.sum()
+}