Bing Maps Isochrones API question/issue

Question

Hi,

We are currently using the Bing Maps Isochrones API to retrieve drive time zones. Although we are using the same API URL, we have observed that the API returns different drive time zones for the same address and the same specified maxtime when the request is made at different times of the day.

https://dev.virtualearth.net/REST/v1/Routes/Isochrones?&optimize=time&timeType=None&travelMode=driving&waypoint=40.574155,-74.1647133&timeUnit=minute&maxTime=10&key={BingMap key}

Our requirement is to receive a consistent drive time zone for the same address and the same specified maxtime, regardless of when the API request is executed.

Could you please advise whether there is a specific parameter or configuration that needs to be included in the API request to ensure consistent results? Additionally, please let us know if there are any best practices or settings we should follow to achieve this behavior.

We appreciate your assistance and look forward to your guidance.

Thanks!

Answer 1

Hi,

Thank you for the update. I hope your question is answered accordingly.

Feel free to reach us anytime.

Best Regards,

Noel

Answer 2

Hi,

Thank you for sharing your question. I understand how frustrating it can be to receive different drive‑time isochrone results even when using the same address and maxTime, especially when your application depends on consistency and accuracy.

The variation you are observing is expected behavior because the Bing Maps Isochrones API incorporates current and predicted traffic conditions, which naturally change throughout the day and influence calculated travel times. This aligns with Microsoft’s official guidance, noting that predictive traffic affects isoline polygons and leads to different results when queries are made at different times.

To achieve consistent results independent of the request time, you can include the dateTime parameter in your API call. This tells the service to calculate the isochrone using a fixed point in time rather than relying on real‑time or predicted traffic. Microsoft’s examples for isochrone generation also highlight using a specific dateTime to control the traffic model used during calculation.

If traffic variation is not needed for your use case, another option is to avoid time‑based isochrones and instead use distance‑based calculations, since these do not depend on traffic conditions and provide fully deterministic results.

To help you further, could you confirm whether your scenario truly requires travel‑time‑based isochrones, or if distance‑based polygons could also meet your requirements?

Please feel free to share your current request URL or any additional requirements, and I’ll be glad to help refine the optimal parameter configuration for your setup.

 

Best Regards,

Noel

Answer 3

The inconsistency in the drive time zones returned by the Bing Maps Isochrones API for the same address and specified maxTime could be attributed to the use of predictive traffic data. When you specify a maxTime, the API utilizes traffic information that can vary throughout the day, leading to different results based on current or predicted traffic conditions at the time of the request.

To achieve more consistent results, consider the following:

1. Use the dateTime parameter: By specifying a dateTime in your request, you can control the traffic data used for the calculation. This allows you to simulate the conditions at a specific time, which can help in achieving consistency across requests.
2. Avoid using predictive traffic data: If you want to avoid variations due to traffic, you might consider using a distance-based isochrone instead of a time-based one, as distance-based calculations do not rely on traffic conditions.
3. Testing at the same time: If you are testing the API, try to make requests at the same time of day to minimize variations due to traffic conditions.

These practices should help you achieve more consistent drive time zones for the same address and specified maxTime.

---

References:

• Calculate an Isochrone
• Isochrone Example