diff --git a/.changeset/rich-peas-return.md b/.changeset/rich-peas-return.md
new file mode 100644
index 0000000..beb9cf0
--- /dev/null
+++ b/.changeset/rich-peas-return.md
@@ -0,0 +1,5 @@
+---
+'tings': minor
+---
+
+Added `toDebugString`.
diff --git a/package-lock.json b/package-lock.json
index 78d6777..6375a19 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -13787,6 +13787,9 @@
       "name": "tings",
       "version": "9.1.0",
       "license": "MIT",
+      "dependencies": {
+        "is-plain-obj": "^4.1.0"
+      },
       "devDependencies": {
         "@types/node": "^20.10.5",
         "rimraf": "^5.0.5",
@@ -13805,6 +13808,17 @@
         "undici-types": "~5.26.4"
       }
     },
+    "package/node_modules/is-plain-obj": {
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/is-plain-obj/-/is-plain-obj-4.1.0.tgz",
+      "integrity": "sha512-+Pgi+vMuUNkJyExiMBt5IlFoMyKnr5zhJ4Uspz58WOhBF5QoIZkFyNHIbBAtHwzVAgk5RtndVNsDRN61/mmDqg==",
+      "engines": {
+        "node": ">=12"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
     "package/node_modules/vite": {
       "version": "5.0.10",
       "resolved": "https://registry.npmjs.org/vite/-/vite-5.0.10.tgz",
diff --git a/package/package.json b/package/package.json
index 7652523..102d311 100644
--- a/package/package.json
+++ b/package/package.json
@@ -30,6 +30,9 @@
     "test": "vitest",
     "typecheck": "tsc --noEmit"
   },
+  "dependencies": {
+    "is-plain-obj": "^4.1.0"
+  },
   "devDependencies": {
     "@types/node": "^20.10.5",
     "rimraf": "^5.0.5",
diff --git a/package/source/index.ts b/package/source/index.ts
index 2ad30f0..95609b1 100644
--- a/package/source/index.ts
+++ b/package/source/index.ts
@@ -10,6 +10,7 @@ export { checkUrlAbsolute } from './check-url-absolute.js'
 export { generateIntegers } from './generate-integers.js'
 export { sleep } from './sleep.js'
 export { toCompactCase } from './to-compact-case.js'
+export { toDebugString } from './to-debug-string.js'
 export { toLetters } from './to-letters.js'
 export { toNumber } from './to-number.js'
 export { toOrdinal } from './to-ordinal.js'
diff --git a/package/source/to-debug-string.test.ts b/package/source/to-debug-string.test.ts
new file mode 100644
index 0000000..8401275
--- /dev/null
+++ b/package/source/to-debug-string.test.ts
@@ -0,0 +1,55 @@
+import { expect, test } from 'vitest'
+
+import { toDebugString } from './to-debug-string.js'
+
+const cases = [
+  ['4', '4'],
+  [undefined, 'undefined'],
+  [null, 'null'],
+  [Symbol(42), 'Symbol(42)'],
+  [false, 'false'],
+  [true, 'true'],
+  [0, '0'],
+  [BigInt('123'), '123n'],
+  [() => null, '() => null'],
+  [(a: unknown) => a, '(a) => a'],
+  [
+    function func() {
+      return 'string'
+    },
+    `function func() {
+      return "string";
+    }`,
+  ],
+  [
+    {
+      a: '4',
+      b: undefined,
+      c: null,
+      d: Symbol(42),
+      e: false,
+      f: true,
+      g: 0,
+      h: BigInt('100000000000000000000000000123'),
+      i: { a: undefined },
+    },
+    '{"a":"4","b":"undefined","c":"null","d":"Symbol(42)","e":"false","f":"true","g":"0","h":"100000000000000000000000000123n","i":{"a":"undefined"}}',
+  ],
+  [
+    [
+      '4',
+      undefined,
+      null,
+      Symbol(42),
+      false,
+      true,
+      0,
+      { a: undefined, m: BigInt('100000000000000000000000000123') },
+    ],
+    '["4","undefined","null","Symbol(42)","false","true","0",{"a":"undefined","m":"100000000000000000000000000123n"}]',
+  ],
+] as const
+
+test.each(cases)('%s is %s', (input, expected) => {
+  expect(toDebugString(input)).toBe(expected)
+})
diff --git a/package/source/to-debug-string.ts b/package/source/to-debug-string.ts
new file mode 100644
index 0000000..b0c98be
--- /dev/null
+++ b/package/source/to-debug-string.ts
@@ -0,0 +1,37 @@
+import isPlainObject from 'is-plain-obj'
+
+/**
+ * WIP
+ * @category String
+ * @example
+```ts
+import { toDebugString } from 'tings'
+
+WIP
+```
+ */
+export function toDebugString(input: unknown): string {
+  if (typeof input === 'string') {
+    return input
+  }
+
+  if (typeof input === 'bigint') {
+    return `${input.toString()}n`
+  }
+
+  if (isPlainObject(input)) {
+    return `{${Object.entries(input).map(([key, value]) =>
+      isPlainObject(value)
+        ? `"${key}":${toDebugString(value)}`
+        : `"${key}":"${toDebugString(value)}"`,
+    )}}`
+  }
+
+  if (Array.isArray(input)) {
+    return `[${input.map((value) =>
+      isPlainObject(value) ? toDebugString(value) : `"${toDebugString(value)}"`,
+    )}]`
+  }
+
+  return String(input)
+}