diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9801d3f..0c16e2a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## v2.4.3
+
+- Fixed replacer function receiving array keys as number instead of string
+
 ## v2.4.2
 
 - Improved ESM TypeScript types.
diff --git a/index.js b/index.js
index 36a1dc8..bd2aa1d 100644
--- a/index.js
+++ b/index.js
@@ -266,11 +266,11 @@ function configure (options) {
           const maximumValuesToStringify = Math.min(value.length, maximumBreadth)
           let i = 0
           for (; i < maximumValuesToStringify - 1; i++) {
-            const tmp = stringifyFnReplacer(i, value, stack, replacer, spacer, indentation)
+            const tmp = stringifyFnReplacer(String(i), value, stack, replacer, spacer, indentation)
             res += tmp !== undefined ? tmp : 'null'
             res += join
           }
-          const tmp = stringifyFnReplacer(i, value, stack, replacer, spacer, indentation)
+          const tmp = stringifyFnReplacer(String(i), value, stack, replacer, spacer, indentation)
           res += tmp !== undefined ? tmp : 'null'
           if (value.length - 1 > maximumBreadth) {
             const removedKeys = value.length - maximumBreadth - 1
diff --git a/test.js b/test.js
index f8e4f95..1321c3c 100644
--- a/test.js
+++ b/test.js
@@ -317,6 +317,7 @@ test('replacer removing elements and indentation', function (assert) {
 
 test('replacer removing all elements', function (assert) {
   const replacer = function (k, v) {
+    assert.type(k, 'string')
     if (k !== '') return
     return k
   }