Problem: The Hassle of Manually Checking Exchange Rates Every Day
Every morning when buyer quote requests came in, our team had to open exchange rate websites on Windows devices, check current rates, and manually enter them into spreadsheets. Especially handling three currencies (USD, EUR, CNY) regularly, we spent over 30 minutes daily just on rate lookups.
"Could this process be automated?" That's where it started.
Solution: Claude Code + Google Sheets API Integration
Step 1: Create a Basic Structure in Google Sheets
First, we built a simple table in Google Sheets.
| Currency | KRW Rate | Last Updated | Auto-calculated Amount |
|----------|----------|--------------|------------------------|
| USD | (auto) | (auto) | (auto) |
| EUR | (auto) | (auto) | (auto) |
| CNY | (auto) | (auto) | (auto) |
Step 2: Write a Simple Script with Claude Code
We entered the following instruction in the Claude Code interface.
"Can you write a Python script that automatically puts the latest exchange rates into Google Sheets? It needs to update USD, EUR, and CNY rates based on Korean Won, refresh every hour, and record update times."
The code generated by Claude Code was extremely clean.
import requests
from datetime import datetime
from google.colab import auth
import gspread
# Authentication (set Google Sheets access permissions)
auth.authenticate_user()
gc = gspread.authorize(auth.default()[0])
# Fetch data from exchange rate API (example: Open Exchange Rates)
api_key = "your_api_key_here"
url = f"https://api.exchangerate-api.com/v4/latest/KRW"
response = requests.get(url)
rates = response.json()["rates"]
# Open Google Sheets
sh = gc.open("exchange_rates_automation").sheet1
# Update data
sh.update_cell(2, 2, round(rates["USD"], 2)) # USD rate
sh.update_cell(3, 2, round(rates["EUR"], 2)) # EUR rate
sh.update_cell(4, 2, round(rates["CNY"], 2)) # CNY rate
# Record update time
sh.update_cell(2, 3, datetime.now().strftime("%H:%M"))
sh.update_cell(3, 3, datetime.now().strftime("%H:%M"))
sh.update_cell(4, 3, datetime.now().strftime("%H:%M"))
print("Exchange rate update complete")
Step 3: Set Up Automatic Execution on Windows Device
We registered the script generated by Claude Code in Windows Task Scheduler.
• Open "Task Scheduler"
• Select "Create Basic Task"
• Set it to run the Python script above every hour
• Limit execution time from 8 AM to 6 PM
Step 4: Add Auto-Calculation Formulas in Google Sheets
Now that rates update automatically, the next step was automating quote calculations.
For example, we added an auto-calculation formula for "Base Price × Exchange Rate = KRW Price."
=B2 * C2
This way, whenever the exchange rate changes in real-time, the final quote amount automatically recalculates.
Results: 80% Time Reduction
• Before: Over 30 minutes daily for rate checks and manual input
• After: Within 5 minutes daily (final review only)
Especially when buyers urgently request price recalculations, we no longer need to say "Give me a moment, let me check the rates again." The latest rates are already in Google Sheets.
Tip: Other Data Can Be Automated the Same Way
This method works not just for exchange rates, but also for:
• Shipping costs (integrate logistics provider APIs)
• Inventory quantities (connect warehouse management systems)
• Customer tiers (auto-analyze order history)
• Buyer credit scores (auto-score transaction records)
"Even though we're not developers, if you know the word 'API,' Claude Code will handle the rest."
The Hamsters team now operates 5+ automation workflows using this approach.