Draw a circle of any size around an address or point on the map: a 5-mile delivery zone, a 25 km commute radius or a 100 nautical mile range. Add several rings per circle and several circles, check whether a place falls inside, then copy a share link or export KML or GeoJSON.
Map images could not load. Circles, distances and exports still work.
Comma-separated radii, e.g. 1, 3, 5
Circles 0
No circles yet. Click the map or press Add circle at map centre.
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How to use the Map Radius Tool
Set your rings: type the radii for new circles (e.g. 5, 10, 25) and pick the unit.
Place a circle: click the map, search an address, or press Add circle at my location.
Adjust it: drag the centre dot to move it, or edit the name, radii, unit, exact centre coordinates and colour in the list.
Check a place: switch to Check a point and click the map (or search) to see how far it is from each centre and which rings contain it.
Share or export: copy the share link, or download KML for Google Earth or GeoJSON for GIS apps.
How the radius circles are drawn
A radius circle is the set of all points at the same great-circle distance from a centre. For each ring the tool walks around the centre in 144 steps and computes each outline point with the destination-point formula on a sphere of radius R = 6,371,008.8 m:
φ₂ = asin(sin φ₁ · cos δ + cos φ₁ · sin δ · cos θ)
λ₂ = λ₁ + atan2(sin θ · sin δ · cos φ₁, cos δ − sin φ₁ · sin φ₂)
Here φ is latitude, λ is longitude, θ is the bearing from the centre and δ = radius ÷ R is the angular distance. Because the outline is computed on the globe and only then projected onto the flat map, the shape is right everywhere: a 500 mile circle around Anchorage looks very tall on the map, yet every edge point really is 500 miles away.
Ring statistics use the same curved-Earth model. Circumference = 2πR · sin(r/R) and area = 2πR² · (1 − cos(r/R)). For circles up to a few hundred miles these agree with the flat formulas 2πr and πr² to better than 0.1%.
Radius reference: area and circumference
Radius
Diameter
Circumference
Area
Typical use
1 mile (1.61 km)
2 mi
6.28 mi
3.14 mi² (2,011 acres)
Walkable neighbourhood, school zone
3 miles (4.83 km)
6 mi
18.85 mi
28.27 mi²
Local delivery, short bike ride
5 miles (8.05 km)
10 mi
31.42 mi
78.54 mi²
Restaurant delivery zone, service area
10 miles (16.09 km)
20 mi
62.83 mi
314.16 mi²
Commute range, realtor search area
25 miles (40.23 km)
50 mi
157.08 mi
1,963.50 mi²
Metro area, job search radius
50 km (31.07 mi)
100 km
314.16 km
7,853.98 km²
Regional coverage, day trips
100 nm (185.2 km)
200 nm
628.32 nm
31,416 nm²
Boating and small-aircraft range planning
Ideas for using radius rings
Service and delivery areas: draw your 5, 10 and 15 mile tiers from the shop, then check a customer's address with Check a point.
House hunting: put a circle around both workplaces; the overlap shows where a fair commute is possible for each person.
Travel and events: mark everything within an hour's drive (roughly 40 to 50 miles straight-line on highways) of a hotel or venue.
Hobby radio, drones and boating: visualise range limits in nautical miles or kilometers, remembering that real coverage depends on terrain and rules.
Frequently asked questions
How do I draw a radius on a map?
Type the radius you want (for example 10) in Rings for new circles, choose miles or kilometers, then click the place on the map or search its address. The circle appears instantly. You can add more rings by typing several values separated by commas, such as 5, 10, 25.
Why does my circle look like an oval on the map?
It is a true circle on the Earth, drawn on a Web Mercator map that stretches distances more the farther you are from the equator. Small circles look round, but large ones look taller than wide and slightly egg-shaped, because the northern half is stretched more than the southern half (in the Northern Hemisphere). Every point on the outline is exactly the chosen distance from the centre.
How accurate are the circles?
Each ring is computed with the spherical destination-point formula on a mean Earth radius of 6,371.0088 km, using 144 points around the edge. Compared with the exact WGS84 ellipsoid, the radius differs by at most about 0.5% (usually much less), which is well under the width of the line for local and regional circles.
What area does a 10 mile radius cover?
A circle's area is π × r². A 10 mile radius covers about 314.16 square miles (813.7 km²), a 5 mile radius about 78.54 square miles, and a 25 mile radius about 1,963.5 square miles. The tool shows the exact area of each ring, using the curved-Earth cap formula 2πR²(1 − cos(r/R)), which matches π × r² for local circles.
Can I check whether an address is inside the radius?
Yes. Switch the map mode to Check a point and click the location, or type the address in the search box. A pin appears and the panel lists the straight-line distance to every circle centre and which rings the point falls inside. Drag the pin to test other spots.
How do I share or save my circles?
Copy share link puts every circle (centre, rings, unit, colour and name) into the page address, so anyone who opens it sees the same map. Your circles are also remembered in this browser. Download KML to open them in Google Earth or import into a custom map, or GeoJSON for GIS software.
Is the radius the same as driving distance?
No. The radius is a straight-line (as-the-crow-flies) distance. Travel distance by road is usually 20 to 40 percent longer, more in hilly areas or around lakes and rivers. For example, a home 10 miles away on the circle may be 13 or 14 miles away by car.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.