What This Isoline Calculator Does
An isoline is a reachable boundary around one map point. It answers a practical question. How far can a person, vehicle, or bike travel from here? This calculator prepares a HERE Isoline request and also gives a mathematical estimate. That estimate is useful before an API call. It helps you test ranges, speeds, and expected coverage.
Why Isoline Math Matters
A simple circle is not a real road network. Roads curve, barriers block movement, and traffic changes time. Still, a circle estimate is helpful for checking input scale. The calculator converts time, distance, or consumption into an estimated radius. Then it computes area and perimeter from that radius. When an API response is available, encoded polygon points can also be decoded. The page can then estimate polygon area with a local map projection.
Advanced Inputs
The form supports latitude, longitude, travel mode, routing mode, range type, range values, speed, and efficiency. Time ranges use seconds. Distance ranges use meters. Consumption ranges use the selected unit assumption. You may enter several ranges with commas. This creates a tiered output. Each tier can be compared in the result table.
Developer Workflow
Use this page while building map search tools, delivery planning screens, store locators, or service zones. First enter a center point. Then choose whether the isoline moves outward from an origin or inward toward a destination. Add an API key only when you want a live request. Otherwise, the calculator still builds the request URL and local estimates.
Export and Review
The CSV export is useful for spreadsheets. The PDF export is useful for client notes. Both include the center, range settings, radius, area, perimeter, and polygon measurements when available. Keep results as estimates until you verify live routing output.
Best Practices
Start with small ranges. Compare time and distance modes. Use realistic average speeds. For cars, remember traffic can change results. For walking, keep speed lower. For trucks, use a proper transport mode and avoid unrealistic assumptions. Always validate important service areas against the returned polygon before publishing. Store API keys securely in production. Avoid exposing private keys in public repositories, logs, or page source. Review rate limits and usage costs before enabling public access.