The script processes financial data through a specific order of operations to ensure the final result is mathematically sound:
Subtotal & Adjustment Logic: The calculator first takes the base bill and applies any flat-rate discounts. It then calculates the tax based on a percentage of that adjusted subtotal, ensuring users aren't taxed on money they didn't spend.
Dynamic Tip Scaling: Unlike basic apps, this tool offers both quick-select presets (10% to 25%) and a "Custom" toggle. This flexibility allows for varying service standards across different cultures and dining contexts.
Weighted Grand Totals: The grand total is derived by summing the adjusted subtotal, the calculated tax, and the tip. This figure is then divided by the person count (managed via a user-friendly increment/decrement counter).
Detailed Transparency Breakdown: One of the standout features is the Per-Person Breakdown. It doesn't just show a final number; it lists out the share for each individual, which is incredibly useful for group payment apps or cash collection.
Designed with a "mobile-first" philosophy, the interface is straightforward and requires zero learning curve:
Enter the Bill: Input the total amount from your receipt.
Adjust for Extras: Enter the tax percentage (if not already included) and any discounts or coupons you used.
Choose Your Tip: Tap one of the percentage buttons. If you want to tip a specific odd amount, use the "Custom" button to reveal a manual input field.
Set the Group Size: Use the + and − buttons to select how many people are sharing the bill.
Review the Split: Click "Calculate & Split" to see exactly what each person owes and a line-by-line breakdown of the total costs.