A drive time map shows everywhere you can get to from a point within a given time. Instead of a circle, you get a shaded zone that follows the roads, called an isochrone. That’s what the drive time map draws, by car, by bike or on foot, with up to four time limits at once. It’s the right tool for questions like “which neighborhoods are within 20 minutes of the office?” or “how far can we deliver in half an hour?”. Here’s how to make one, a real example and why a radius circle overestimates.
What Google Maps can and can’t show you
Google Maps times one trip at a time: with Directions you enter a start and a destination, and each route shows its estimated travel time. That answers “how long from here to there?”, but not “where can I get to in 30 minutes?”. For that you’d have to try destination after destination. A drive time map does all of them at once.
How to make a drive time map
- Open the drive time map.
- Choose the starting point: search for an address or a place, use your location or tap the map.
- Pick the travel mode: Car, Bike or Walk.
- Choose up to four times, from 1 to 60 minutes (or distances along the road, if you prefer miles).
- Read each zone’s area and how far it reaches in a straight line. Copy the link to share it, or download the zones as GeoJSON.
An example: 15, 30 and 45 minutes from Denver
From the Colorado State Capitol, by car, worked out on October 31, 2026:
| Time by car | Area you can reach | Farthest point (straight line) |
|---|---|---|
| 15 minutes | 96 sq mi | 10.9 miles |
| 30 minutes | 793 sq mi | 24.9 miles |
| 45 minutes | 2,002 sq mi | 42.0 miles |
Times assume clear roads at each road’s normal speed, with no traffic, lights or stops.
Why a radius circle overestimates
A circle assumes you can go the same distance in every direction. Roads don’t work that way: they follow valleys, cross rivers at bridges and leave gaps between highways. Compare each zone with a circle that reaches just as far:
- The 30-minute zone reaches 24.9 miles. A circle with that radius covers about 1,948 square miles; the zone covers 793, 41% of it.
- The 15-minute zone reaches 10.9 miles; a circle that size would cover about 373 square miles, almost four times the 96 the zone covers.
- The 45-minute zone reaches 42.0 miles; the circle would cover about 5,542 square miles, almost three times the 2,002 of the zone.
So if you draw “30 minutes” as a 25-mile circle, you’re promising more than twice the area you can actually reach in that time. For a delivery area or a commute limit, use the drive time map; for “within X miles” rules, the radius guide shows how to draw the circle.
What people use it for
- House hunting: set your office or your kids’ school as the starting point and see which neighborhoods fall within 20 minutes.
- Delivery and service areas: show how far you can get in half an hour from your store or workshop.
- Choosing a location: compare how much ground two storefronts cover within a 10-minute walk.
- Meeting up: to find the spot where two or three people drive the same time, use meet in the middle, explained in the halfway point guide.
How it’s worked out
The zones come from Valhalla, an open-source routing engine, running on the OpenStreetMap road network on FOSSGIS’s public server. From the starting point it follows every road or path open to your travel mode (cars stay off footpaths, bikes off freeways), notes how long it takes to reach each stretch, and draws the outline of everything within each limit. To know how many people live inside a circle around the same point, try population in a radius.