Every month I used to spend 2-3 hours going through bank statements and categorizing expenses for tax purposes. "Is that $34.99 charge from AWS or personal? Let me scroll back and check..."

This script ended that. It reads your bank CSV export and auto-categorizes everything.

How It Works

Most banks let you export transactions as CSV. The format varies, but they all have: date, description, amount. My script reads that CSV and applies pattern matching to categorize each transaction.

import csv import re from collections import defaultdict from datetime import datetime

# Define your category rules (regex patterns → category) CATEGORIES = { " Software & Subscriptions " : [ r " AWS|AMAZON WEB|GOOGLE CLOUD|DIGITALOCEAN|HEROKU " , r " GITHUB|GITLAB|NOTION|FIGMA|ADOBE|CANVA " , r " STRIPE|GUMROAD|SHOPIFY " , r " ZOOM|SLACK|DISCORD|LOOM " , ], " Advertising " : [ r " GOOGLE ADS|FACEBOOK ADS|META PLATFORMS|TWITTER ADS " , r " LINKEDIN|REDDIT ADS " , ], " Office & Equipment " : [ r "…