diff --git a/src/wxsy.net/extract.py b/src/wxsy.net/extract.py
new file mode 100644
index 0000000..44fdd8e
--- /dev/null
+++ b/src/wxsy.net/extract.py
@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+"""
+Extract data from raw html content.
+
+    USAGE: python3 extract.py [CATALOG] [HTML_DIR] [OUTPUT_DIR]
+"""
+
+import os
+import re
+import sys
+import json
+from logger import logger
+from bs4 import BeautifulSoup
+
+
+def splitHtml(rawHtml: str) -> dict:  # extract from raw html content
+    html = BeautifulSoup(rawHtml, 'lxml')
+    script = html.select('script')[9].text  # js code with chapter info
+    info = {
+        'title': html.select('div[class="pt-read-title"]')[0].contents[1].contents[0].attrs['title'],
+        'preId': re.search(r'window\.__PREVPAGE = "(\d*)"', script)[1],
+        'nextId': re.search(r'window\.__NEXTPAGE = "(\d*)"', script)[1],
+        'myId': re.search(r'window\.chapterNum = (\d+)', script)[1],
+        'content': [x.text.strip() for x in html.select('p[class="content_detail"]')],
+    }
+    if info['title'] != re.search(r'window\.chapterName = \'(.+)\'', script)[1]:  # chapter title check
+        logger.error('Title error -> %s' % info['title'])
+    return info
+
+
+catalog = json.loads(open(sys.argv[1]).read())  # load catalog
+
+for _, chapterId in catalog.items():  # traverse all chapters
+    logger.info('Analyse chapter `%s`' % chapterId)
+    with open(os.path.join(sys.argv[3], '%s.json' % chapterId), 'w') as fileObj:
+        htmlFile = os.path.join(sys.argv[2], '%s.html' % chapterId)
+        fileObj.write(json.dumps(
+            splitHtml(open(htmlFile).read())
+        ))