diff --git a/packages/core/src/utility.ts b/packages/core/src/utility.ts
index bdf8498..82364d5 100644
--- a/packages/core/src/utility.ts
+++ b/packages/core/src/utility.ts
@@ -18,6 +18,15 @@ export const hashOutpoints = (outpoints: Outpoint[]): Buffer => {
     return createHash('sha256').update(outpointBuffer).digest();
 };
 
+export const createTaggedHash = (tag: string, buffer: Buffer): Buffer => {
+    const tagHash = createHash('sha256').update(tag, 'utf8').digest();
+    return createHash('sha256')
+        .update(tagHash)
+        .update(tagHash)
+        .update(buffer)
+        .digest();
+};
+
 export const calculateSumOfPrivateKeys = (keys: PrivateKey[]): Buffer => {
     const negatedKeys = keys.map((key) => {
         const privateKey = Buffer.from(key.key, 'hex');
diff --git a/packages/core/test/fixtures/utility.ts b/packages/core/test/fixtures/utility.ts
index 3e3ede4..40db486 100644
--- a/packages/core/test/fixtures/utility.ts
+++ b/packages/core/test/fixtures/utility.ts
@@ -115,3 +115,24 @@ export const inputPrivateKeys = [
             'ee55616ce5a93e508f03f21949ecbe70a2a0b107b6e1df5d98b4e4da4adaca1b',
     },
 ];
+
+export const createTaggedHashData = [
+    {
+        tag: 'tag',
+        hex: '0000000000000000000000000000000000000000000000000000000000000000',
+        expected:
+            '25a36caa510aee2994cd72a09782258d8621d99a9df9c5d7428ef6a7b026f7bb',
+    },
+    {
+        tag: 'tag',
+        hex: 'ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff',
+        expected:
+            'f5f36a052776e5652c4250f4c49a78415da4c366531839c5d27ba6aafefe3859',
+    },
+    {
+        tag: 'tag',
+        hex: '25a36caa510aee2994cd72a09782258d8621d99a9df9c5d7428ef6a7b026f7bbf5f36a052776e5652c4250f4c49a78415da4c366531839c5d27ba6aafefe3859',
+        expected:
+            'de9cd3236391a236466fbc0d3c79e62503cde0270c6df0c4a7d3d10ca94404e4',
+    },
+];
diff --git a/packages/core/test/utility.spec.ts b/packages/core/test/utility.spec.ts
index 4014d43..729411b 100644
--- a/packages/core/test/utility.spec.ts
+++ b/packages/core/test/utility.spec.ts
@@ -1,10 +1,15 @@
 import {
     calculateSumOfPrivateKeys,
+    createTaggedHash,
     hashOutpoints,
     Outpoint,
     PrivateKey,
 } from '../src';
-import { inputPrivateKeys, outpoints } from './fixtures/utility';
+import {
+    createTaggedHashData,
+    inputPrivateKeys,
+    outpoints,
+} from './fixtures/utility';
 
 describe('Utility', () => {
     it.each(outpoints)(
@@ -24,4 +29,12 @@ describe('Utility', () => {
             expect(sum.toString('hex')).toBe(expected);
         },
     );
+
+    it.each(createTaggedHashData)(
+        'should calculate tagged hash',
+        ({ tag, hex, expected }) => {
+            const taggedHash = createTaggedHash(tag, Buffer.from(hex, 'hex'));
+            expect(taggedHash.toString('hex')).toBe(expected);
+        },
+    );
 });