diff --git a/src/filters/misc.ts b/src/filters/misc.ts
index 57ed57812..a80dd6ece 100644
--- a/src/filters/misc.ts
+++ b/src/filters/misc.ts
@@ -9,13 +9,19 @@ function defaultFilter<T1 extends boolean, T2> (this: FilterImpl, value: T1, def
   return isFalsy(value, this.context) ? defaultValue : value
 }
 
-function json (value: any, space = 0) {
-  return JSON.stringify(value, null, space)
+function json (this: FilterImpl, value: any, space = 0) {
+  const memoryLimit = this.context.memoryLimit
+  return JSON.stringify(value, (_key, val) => {
+    memoryLimit.use(typeof val === 'string' ? val.length : 1)
+    return val
+  }, space)
 }
 
-function inspect (value: any, space = 0) {
+function inspect (this: FilterImpl, value: any, space = 0) {
+  const memoryLimit = this.context.memoryLimit
   const ancestors: object[] = []
   return JSON.stringify(value, function (this: unknown, _key: unknown, value: any) {
+    memoryLimit.use(typeof value === 'string' ? value.length : 1)
     if (typeof value !== 'object' || value === null) return value
     // `this` is the object that value is contained in, i.e., its direct parent.
     while (ancestors.length > 0 && ancestors[ancestors.length - 1] !== this) ancestors.pop()
diff --git a/test/integration/liquid/dos.spec.ts b/test/integration/liquid/dos.spec.ts
index a3ac56804..65d78adb5 100644
--- a/test/integration/liquid/dos.spec.ts
+++ b/test/integration/liquid/dos.spec.ts
@@ -114,6 +114,22 @@ describe('DoS related', function () {
       expect(() => liquid.parseAndRenderSync('{{ array | array_to_sentence_string }}', { array }))
         .toThrow('memory alloc limit exceeded')
     })
+    it('should charge json serialization of concat-doubled arrays', () => {
+      const liquid = new Liquid({ memoryLimit: 1e4 })
+      const src = '{%- assign a = s | split: "NOSEP" -%}' +
+        '{%- assign a = a | concat: a -%}{%- assign a = a | concat: a -%}{%- assign a = a | concat: a -%}' +
+        '{{ a | json | size }}'
+      expect(() => liquid.parseAndRenderSync(src, { s: 'a'.repeat(5000) }))
+        .toThrow('memory alloc limit exceeded')
+    })
+    it('should charge inspect serialization of concat-doubled arrays', () => {
+      const liquid = new Liquid({ memoryLimit: 1e4 })
+      const src = '{%- assign a = s | split: "NOSEP" -%}' +
+        '{%- assign a = a | concat: a -%}{%- assign a = a | concat: a -%}{%- assign a = a | concat: a -%}' +
+        '{{ a | inspect | size }}'
+      expect(() => liquid.parseAndRenderSync(src, { s: 'a'.repeat(5000) }))
+        .toThrow('memory alloc limit exceeded')
+    })
     it('should charge strip_html input length to memoryLimit', () => {
       const liquid = new Liquid({ memoryLimit: 100 })
       expect(() => liquid.parseAndRenderSync('{{ s | strip_html }}', { s: 'a'.repeat(200) }))