Lease Mileage Calculator

Optional: Use URL Parameters for Autofill/Auto-Run

How it works: Append query parameters to the URL (e.g., after index.html) to pre-fill fields. If all three core params are provided, it auto-calculates on load. Use format=json for raw JSON output (API mode).

Core Parameters:
- startDate: YYYY-MM-DD (e.g., 2025-01-01)
- termMonths: Number of months (e.g., 36)
- annualMiles: Annual allowance (e.g., 12000)
Output Modes:
- format: html (default: Web UI) or json (raw JSON for curl/scripts).
Partial vs. Full: Use any subset to autofill—manual calc still needed unless all core params are set. JSON mode requires all core params.

Examples:

Autofill only term: ?termMonths=36
    
    Full autofill + auto-run (HTML): ?startDate=2025-01-01&termMonths=36&annualMiles=12000
    
    Full + JSON API (curl-friendly): ?startDate=2025-01-01&termMonths=36&annualMiles=12000&format=json

Copy the full URL from your browser's address bar to share pre-filled links. Uses today's date (December 05, 2025) for calcs. JSON output includes currentCap, totalMiles, elapsedDays, etc.