Free Window Awning Calculator and 3D Visualizer

A well-sized window awning isn't simply the largest one that fits. The right design balances three things: how much summer sun it blocks, how much winter sun it lets through, and how much of your outward view it preserves. These four window awning dimensions drive that balance.

Overall awning width should extend beyond your window opening on both sides. That side overhang accounts for the fact that the sun rarely hits a wall dead-on — a wider awning keeps shading the glass as the sun moves across the sky. Projection is how far the awning reaches out from the wall. More projection shades more of the window at midday, but it also extends farther into walkways and patios. Angle is the slope of the awning surface. A steeper angle sheds rain and snow better and can shade more of a tall window, but it also blocks more of the sky. Mounting height — how far above the window opening the awning attaches — changes how low the awning can drop before it covers the glass.

Larger is not automatically better. An oversized awning may block winter sun you'd rather keep, and a deep projection can darken a room more than necessary. You can adjust each dimension and see the tradeoff immediately in the designer.

An exterior window awning blocks sunlight before it reaches the glass. That matters: once sunlight passes through a window, it warms the room and the interior surfaces, and that heat stays. Shading the glass from the outside keeps a meaningful portion of that energy out.

How much heat an awning blocks depends on your latitude, the direction the window faces, the sun's angle throughout the day and season, the awning's projection and angle, and how the awning is mounted relative to the top of the window. A south-facing window in a southern climate sees the sun high overhead at noon in summer, so a moderate projection can shade most of the glass. The same window in a northern state, or a window that faces east or west, sees the sun at a lower angle and may need a different combination of width, projection, and angle.

Awning Creator uses your location and window orientation to model the sun's path, so the awning shade calculator reflects your actual situation rather than a national average.

One of the most useful things a window awning can do is block the high summer sun while letting in the low winter sun. In summer the sun rides high across the sky, and a properly sized awning can shade the glass for most of the hottest hours. In winter the same sun travels a much lower arc — and if the awning is sized correctly, that lower winter sun passes underneath the awning and still reaches the window.

That's why Awning Creator shows Summer Shade and Winter Sun as separate numbers. An awning that maximizes summer shade may also cut into the winter warmth and daylight you want, so the tool lets you compare both at once and find a balance that suits your climate and priorities. Try the window awning calculator to see both numbers for your window.

Any awning that projects from the wall above a window will take up some of your view of the sky. How much depends on the projection, the angle, the mounting height, and how wide the awning extends. A deep, steeply angled awning mounted low can block a noticeable slice of the upper view; a shallower angle mounted higher may preserve more of it.

The awning design tool shows a View Retained number so you can weigh that tradeoff directly against the shade you gain. If preserving an open view matters more to you than maximum shade, you can choose a smaller projection or a gentler angle and watch the View Retained number go up.

The process is designed to take a few minutes:

1. Enter your window width, height, and sill height.
2. Enter your location so the tool can model the sun's path for your latitude.
3. Enter the exact direction your window faces if you can — orientation has a large effect on which hours of the day the glass is exposed.
4. Awning Creator evaluates the solar geometry for your window across the seasons.
5. It recommends practical awning dimensions that balance shade, winter sun, and view.
6. It compares Summer Shade, View Retained, and Winter Sun for the recommended design.
7. You can adjust any dimension and immediately see how the numbers change.

You don't need to know the ideal dimensions in advance — the tool starts with a sensible recommendation and lets you refine it. Calculate your awning size to begin.