How to use the arch generator
Enter the total width of the arch and how tall it should be, then choose the thickness of the arch band. The drawing is a front view: build it upright against a wall or between two pillars, starting from the bottom row. When the height is exactly half the width you get a perfect semicircle (Roman arch). A lower height gives a flat, elliptical arch; a higher one gives a tall, pointed-looking arch.
Where to use arches
- Doorways and gates – a 7-wide, 5-tall arch over a castle gate.
- Bridges – repeat the same arch between supports for a viaduct.
- Windows – small 3–5 wide arches on churches and towers.
- Tunnels and mine entrances – extend the arch backwards to form a vaulted tunnel.
Tip: matching doorways
For a 1-block doorway use an odd width; for a 2-block doorway use an even width. The "opening at the base" value tells you how wide the gap between the legs is.
Frequently asked questions
How do I make a semicircle arch?
Set the height to half of the width. For example, a 15-wide arch that is 8 tall is very close to a perfect semicircle.
Can I make a pointed arch?
Make the arch taller than half its width. The shape becomes a tall ellipse, which reads as a gothic-style arch at small sizes.
How thick should an arch be?
2 blocks looks solid for gates and bridges. 1 block is fine for windows.