📊 ROAS Calculator for Cross-border E-commerce

A free, open-source command-line tool to calculate Return on Ad Spend (ROAS), break-even CPA, profit margins, and multi-channel ad budget allocation — built specifically for cross-border e-commerce sellers.

🌐 Prefer a visual calculator? Use the free online version at kuajingbase.com/en/tools/roas-calculator

Why This Tool?

Most ROAS calculators online are oversimplified — they only divide revenue by ad spend. But cross-border sellers deal with hidden costs that eat into margins:

• 💳 Payment processing fees (Stripe 2.9% + $0.30, PayPal 3.49%, etc.)
• 📦 International shipping costs ($5–$15 per order)
• 🏷️ Platform commissions (Amazon 15%, Shopify 0%)
• 🔄 Refund/chargeback losses (typically 2–5%)
• 💱 Currency conversion fees (0.5–2%)

This calculator factors in all of these to give you a realistic break-even ROAS — not the fantasy number most tools show.

📖 Learn more about cross-border payment fees: Payment Methods Compared

Quick Start

Requirements: Python 3.8+

# Clone the repo
git clone https://github.com/reituman602/roas-calculator.git
cd roas-calculator

# Basic calculation
python roas_calculator.py --price 49.99 --cogs 12.00 --shipping 5.50

# With target ROAS and budget simulation
python roas_calculator.py \
  --price 49.99 \
  --cogs 12.00 \
  --shipping 5.50 \
  --target-roas 3.0 \
  --daily-budget 50 \
  --cpc 1.20 \
  --cvr 0.02

# Multi-channel comparison
python roas_calculator.py \
  --price 49.99 \
  --cogs 12.00 \
  --shipping 5.50 \
  --compare

# JSON output (for piping to other tools)
python roas_calculator.py --price 49.99 --cogs 12.00 --json

Example Output

============================================================
  ROAS CALCULATOR — Cross-border E-commerce Analysis
  https://kuajingbase.com/en/tools/roas-calculator
============================================================

📦 PRODUCT ECONOMICS
  Selling Price:        $49.99
  Total Cost/Unit:      $20.45
  Gross Profit/Unit:    $29.54
  Gross Margin:         59.1%

📊 BREAK-EVEN ANALYSIS
  Break-even ROAS:      1.69x
  Break-even CPA:       $29.54
  (You must spend < $29.54 per sale to profit)

🎯 TARGET ROAS ANALYSIS
  Target ROAS:          3.0x
  Target CPA:           $16.66
  Net Profit/Unit:      $12.88
  Net Margin:           25.8%
  ✅  Profitable! (break-even is 1.69x)

💰 BUDGET SIMULATION (30-day projection)
  Daily Ad Budget:      $50.00
  Expected Daily Sales: 0.8
  Expected Daily Rev:   $41.66
  Expected Daily Profit:$-26.37
  Monthly Profit:       $-791.10
  ⚠️  Projected LOSS — optimize CPC or conversion rate!

Multi-Channel Comparison

Compare ROAS across Google, Facebook, TikTok, and Pinterest ads in one view:

======================================================================
  MULTI-CHANNEL ROAS COMPARISON
======================================================================

Channel          CPC    CVR      CPA   ROAS   Daily P/L
----------------------------------------------------------------------
Google Ads      $1.50   2.5%   $60.00   0.8x    $-25.18 ❌
Facebook Ads    $0.80   1.5%   $53.33   0.9x    $-22.37 ❌
TikTok Ads      $0.40   1.0%   $40.00   1.2x    $-13.07 ❌
Pinterest Ads   $0.60   2.0%   $30.00   1.7x     $-0.46 ❌

📖 Deep dive into ad strategies: TikTok Ads Guide for Cross-border Stores | Facebook Ads vs TikTok Ads

All Parameters

Use as a Python Module

from roas_calculator import ProductMetrics, calculate_roas, format_report

product = ProductMetrics(
    selling_price=49.99,
    cost_of_goods=12.00,
    shipping_cost=5.50,
    payment_fee_rate=0.029,     # Stripe
    platform_fee_rate=0.0,      # Shopify (no commission)
)

result = calculate_roas(
    product,
    target_roas=3.0,
    daily_budget=100,
    avg_cpc=0.80,
    conversion_rate=0.02,
)

print(f"Break-even ROAS: {result.breakeven_roas}x")
print(f"Break-even CPA: ${result.breakeven_cpa}")
print(f"Monthly profit at target: ${result.expected_monthly_profit}")

Common Scenarios for Cross-border Sellers

Shopify Store (Self-hosted)

python roas_calculator.py --price 39.99 --cogs 8.00 --shipping 4.50 \
  --payment-fee 0.029 --platform-fee 0.0 --target-roas 3.0

Amazon FBA

python roas_calculator.py --price 29.99 --cogs 6.00 --shipping 0 \
  --payment-fee 0.0 --platform-fee 0.15 --refund-rate 0.05 --target-roas 4.0

WooCommerce + Stripe

python roas_calculator.py --price 59.99 --cogs 15.00 --shipping 6.00 \
  --payment-fee 0.029 --payment-fixed 0.30 --target-roas 2.5

📖 Need help choosing a platform? Read Shopify vs WooCommerce — Which Is Right for You?

Related Resources

• 🌐 Online ROAS Calculator — Interactive web version with charts
• 💳 Cross-border Payment Guide — Compare Stripe, Airwallex, Wise, Payoneer fees
• 🏪 Build Your First Store — Step-by-step from zero to first sale
• 🌐 Best Hosting for E-commerce — Cloudways, VPS, and shared hosting compared
• 🛠️ 70+ Cross-border Tools Directory — Every tool tested with real data

Contributing

Issues and PRs are welcome! If you have ideas for new features (e.g., currency conversion, LTV projection, cohort analysis), please open an issue.

License

MIT License — free to use, modify, and distribute.

Built with ❤️ by Bob Tong · KuajingBase 跨境基地

A practical resource hub for cross-border e-commerce sellers — store setup, payment solutions, hosting reviews, and growth strategies.