diff --git a/README.md b/README.md
index dd69a30..9600605 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,7 @@ Before submitting a pull request, please make sure the following is done:
 - Fork the repository and create your feature branch from dev.
 - Run `npm install` to have all dependencies.
 - To start development run `npm run test:watch`.
-- Write tests in `src/<scope>/<name>.test.ts` and implementation in `src/<scope>/<name>.ts`.
+- Write tests in `src/<scope>/<name>.spec.ts` and implementation in `src/<scope>/<name>.ts`.
 - Add the documentation page to the `docs/<scope>/<function>.mdx` and update `docs/<scope>/_meta.json` file.
 - Ensure everything is ok `npm run verify`.
 
diff --git a/docs/pages/number/_meta.json b/docs/pages/number/_meta.json
index 4db1c49..aeeceb7 100644
--- a/docs/pages/number/_meta.json
+++ b/docs/pages/number/_meta.json
@@ -1,6 +1,8 @@
 {
   "clamp": "clamp",
   "divide": "divide",
+  "inc": "inc",
+  "dec": "dec",
   "fallback-number": "fallbackNumber",
   "is-in-range": "isInRange",
   "is-negative": "isNegative",
diff --git a/docs/pages/number/dec.mdx b/docs/pages/number/dec.mdx
new file mode 100644
index 0000000..1c30a29
--- /dev/null
+++ b/docs/pages/number/dec.mdx
@@ -0,0 +1,22 @@
+# dec
+
+Decrements the given number by 1. Useful for counters and mathematical operations.
+
+### Import
+
+```typescript copy
+import { dec } from '@fullstacksjs/toolbox';
+```
+
+### Signature
+
+```typescript copy
+function dec(n: number): number {}
+```
+
+### Examples
+
+```typescript copy
+dec(3) // 2
+dec(5) // 4
+```
diff --git a/docs/pages/number/inc.mdx b/docs/pages/number/inc.mdx
new file mode 100644
index 0000000..fd7be3a
--- /dev/null
+++ b/docs/pages/number/inc.mdx
@@ -0,0 +1,22 @@
+# inc
+
+Increments the given number by 1. Useful for counters and mathematical operations.
+
+### Import
+
+```typescript copy
+import { inc } from '@fullstacksjs/toolbox';
+```
+
+### Signature
+
+```typescript copy
+function inc(n: number): number {}
+```
+
+### Examples
+
+```typescript copy
+inc(3) // 4
+inc(5) // 6
+```
diff --git a/src/number/dec.spec.ts b/src/number/dec.spec.ts
new file mode 100644
index 0000000..21a00ac
--- /dev/null
+++ b/src/number/dec.spec.ts
@@ -0,0 +1,8 @@
+import { dec } from './dec';
+
+describe('dec', () => {
+  it('should decrement by 1', () => {
+    expect(dec(2)).toBe(1);
+    expect(dec(5)).toBe(4);
+  });
+});
diff --git a/src/number/dec.ts b/src/number/dec.ts
new file mode 100644
index 0000000..be26d22
--- /dev/null
+++ b/src/number/dec.ts
@@ -0,0 +1,14 @@
+/**
+ * Decrements a number by 1.
+ *
+ * @param {number} n - The number to decrement.
+ * @returns {number} The decremented number.
+ *
+ * @example
+ * dec(3) // 2
+ * dec(5) // 4
+ */
+
+export function dec(n: number): number {
+  return n - 1;
+}
diff --git a/src/number/inc.spec.ts b/src/number/inc.spec.ts
new file mode 100644
index 0000000..af13ed0
--- /dev/null
+++ b/src/number/inc.spec.ts
@@ -0,0 +1,8 @@
+import { inc } from './inc';
+
+describe('inc', () => {
+  it('should increment by 1', () => {
+    expect(inc(0)).toBe(1);
+    expect(inc(5)).toBe(6);
+  });
+});
diff --git a/src/number/inc.ts b/src/number/inc.ts
new file mode 100644
index 0000000..1ff1ae0
--- /dev/null
+++ b/src/number/inc.ts
@@ -0,0 +1,14 @@
+/**
+ * Increments a number by 1.
+ *
+ * @param {number} n - The number to increment.
+ * @returns {number} The incremented number.
+ *
+ * @example
+ * inc(3) // 4
+ * inc(5) // 6
+ */
+
+export function inc(n: number): number {
+  return n + 1;
+}
diff --git a/src/number/index.ts b/src/number/index.ts
index 7141d1f..e3248ef 100644
--- a/src/number/index.ts
+++ b/src/number/index.ts
@@ -1,6 +1,8 @@
 export { clamp } from './clamp.ts';
+export { dec } from './dec.ts';
 export { divide } from './divide.ts';
 export { fallbackNumber } from './fallbackNumber.ts';
+export { inc } from './inc.ts';
 export { isInRange } from './isInRange.ts';
 export { isNegative } from './isNegative.ts';
 export { isPositive } from './isPositive.ts';