Doorway and bridge curve planner

Minecraft Arch Generator & Bridge Arch Calculator

Choose a span, height, and thickness to calculate and create symmetrical pixel arches for entrances, bridges, tunnels, windows, and façades.

Built around a clear opening.
Thickness controls the band of blocks around the curved opening without changing the outside width and height.

15 × 11 Arch
100%
52blocks this layer
15width
11height
20build runs

How to use the Minecraft arch generator & calculator

Width controls the outside span, height controls the rise from the baseline to the crown, and thickness controls the number of blocks around the opening. Build one half from the chart and mirror it across the center line.

Minecraft bridge arch calculator & tunnel design

For structural bridge builds and viaducts, enter the span between river banks or canyon walls as width, and desired water clearance as height. Extend the calculated arch backward to create a vaulted tunnel, aqueduct, or repeat identical spans across multiple piers for large railway bridges.

Doorway and window arches

Odd widths provide one center keystone block at the top. Even widths create a two-block center, which aligns seamlessly with double doors and 2-wide castle gates. Add vertical pillars below the generated curve when the opening needs higher headroom.

Round versus tall arches (Elliptical arches)

Equal width and height produce a rounded semi-circular opening. Increasing height creates a Gothic or Cathedral arch; increasing width produces a flat Roman or basket-handle span. Use the Minecraft oval generator when you need the complete closed ellipse, or the dome generator for full 3D roofs.