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AOI Geometry Requirements

When you create a Standard Area Coverage order, you define your Area of Interest (AOI) by drawing it on the map or uploading a GeoJSON file. That area has to describe a well-formed, sensibly-shaped polygon. The platform checks your geometry as soon as you draw or upload it, so if something is wrong you get immediate, specific feedback and can fix the shape before you submit. You can't place the order until the AOI is valid.

This page explains each requirement and shows what a valid versus invalid AOI looks like.

Why these rules exist

Pathological geometries (polygons with holes, boundaries that cross themselves, extremely long and thin corridors, or millions of vertices) can't be planned or collected reliably. Validating up front means you get immediate, specific feedback instead of a silent failure later in the pipeline.

Placing an Archive order instead?

Archive Imagery orders are validated against a smaller set of rules. See Archive Geometry Requirements.

Requirements at a glance

Requirement Rule
Minimum area The AOI must be at least 50 km²
Maximum area The AOI must not exceed 500 km²
Minimum dimensions At least 5 km wide and 10 km long
Maximum length No longer than 300 km
Bounding box The overall span of the AOI must not exceed 1000 km
No internal holes The polygon must be solid, with no inner rings
Topological integrity The boundary must not self-intersect or overlap
Vertex count At most 500 vertices
Minimum vertices At least 4 vertices
Point spacing Consecutive vertices must be at least 3 km apart
Minimum local width No corridor narrower than 1 km at any point
Aspect ratio The shape must be reasonably compact (not too narrow or winding)
Payload size The GeoJSON file must be 2 MB or smaller

The sections below illustrate the most common reasons an AOI is rejected.

Solid area: no internal holes

In GeoJSON, the first ring of a Polygon is the exterior boundary. Any additional rings are interior rings (holes cut out of the shape). AOIs must be solid: interior rings are not supported.

✅ Valid: a single solid ring

❌ Invalid: contains an interior ring (hole)
Invalid: the second ring is a hole
{
  "type": "Polygon",
  "coordinates": [
    [[-122.4, 37.7], [-122.3, 37.7], [-122.3, 37.8], [-122.4, 37.8], [-122.4, 37.7]],
    [[-122.38, 37.72], [-122.32, 37.72], [-122.35, 37.76], [-122.38, 37.72]]
  ]
}

Rejection message

Polygons with internal holes are not supported. Please provide a solid area.

Topological integrity: no self-intersections

The boundary of the polygon must never cross itself. An "hourglass" or "figure-8" shape crosses its own edge, producing an invalid, non-simple geometry.

✅ Valid: boundary never crosses itself

❌ Invalid: the boundary crosses itself

Rejection message

The boundary self-intersects or contains topological errors. Please check and repair your polygon.

Size: minimum and maximum area

A Standard Area Coverage AOI must cover between 50 km² and 500 km². Areas below the minimum are too small to task efficiently; areas above the maximum exceed what a single order can cover.

< 50 km²

❌ Too small: below 50 km²

50 to 500 km²

✅ Valid: within range

> 500 km²

❌ Too large: above 500 km²

Rejection messages

Standard Area Coverage requires a minimum area of 50 km².
Standard Area Coverage requires a maximum area of 500 km².

The overall span of the AOI (its bounding box) must also stay within 1000 km.

Rejection message

The overall span of your order exceeds the 1000 km limit.

Shape: dimensions, length and compactness

Beyond total area, the shape of the AOI matters. Long, thin, or winding areas are hard to collect. Several rules work together to keep AOIs reasonably compact:

  • Minimum dimensions: at least 5 km wide and 10 km long.
  • Maximum length: no longer than 300 km.
  • Minimum local width: no corridor narrower than 1 km anywhere in the shape.
  • Aspect ratio: the shape must be compact enough (√Area / Perimeter ≥ 0.25); narrow slivers and winding corridors are rejected.

✅ Valid: compact area

❌ Invalid: too narrow / low aspect ratio

❌ Invalid: winding corridor narrower than 1 km

Rejection messages

The area must be at least 5 km wide and 10 km long.
Maximum length for a single order is 300 km.
The area contains corridors narrower than 1 km.
The area is too narrow or winding. Please submit a more compact polygon.

Vertices and point spacing

The outline must be described efficiently. Street-grid tracings and over-detailed outlines with thousands of points are rejected, and consecutive vertices can't be nearly on top of each other.

  • Vertex count: at most 500 vertices, and at least 4.
  • Point spacing: consecutive vertices must be at least 3 km apart.

✅ Valid: few, well-spaced vertices

❌ Invalid: too many or too-close vertices

Rejection messages

Too many points. Please simplify the outline of your area.
A minimum of 4 vertices is required.
Points are too close together. Minimum spacing is 3 km.

File size

The GeoJSON file you upload must be 2 MB or smaller. Oversized files are usually a symptom of an over-detailed outline; simplify the polygon before submitting.

Rejection message

The geometry file exceeds the 2MB limit. Please simplify or compress the file.

Getting it right the first time

If an AOI is rejected, the platform tells you exactly which rule(s) failed, and all failing rules are reported at once, not just the first. Simplify and reshape your polygon so it is a single, solid, compact area between 50 and 500 km², and it will pass.