A Miro alternative for circuit diagrams (where the wires actually route)

TLDR: If you're using Miro, Lucidchart, or draw.io to sketch a circuit, an ERD, or a floorplan, you've hit the wall: the "wires" are just lines, so they cross, tangle, and drift out of alignment every time you nudge a box. A tool built for schematics snaps wires to actual ports and routes them cleanly. If you also don't want a $200/seat CAD license or to upload your IP to the cloud, Schema Editor runs in your browser, saves plain SVG, and opens in seconds.

Why general diagram tools fight you on schematics

Miro, Figma, and Lucidchart are excellent for whiteboards and org charts. They fall apart on anything with connections that matter, because to them a wire is a decorative line between two shapes. That means:

• Move a component and its wires don't follow the ports — they drift or detach.
• Wires cross each other into an unreadable tangle with no auto-routing.
• There's no concept of a pin, a port, or a net — so nothing enforces that a connection is even valid.

You end up spending more time nudging lines back into place than actually designing.

What you actually search for

Engineers describe this in a lot of ways — "Miro alternative for circuit diagrams," "ERD tool with auto-routing," "diagram tool where wires snap to ports," "draw.io alternative for schematics." They're all the same underlying need: a diagram tool that understands connections, not just shapes and lines.

What Schema Editor does differently

Schema Editor is built around connections from the start:

• Wires snap to ports and auto-route. Move a component and the wiring follows and re-routes cleanly instead of tangling.
• It knows what a valid connection is. For circuits, it checks the wiring as you draw — it flags shorted outputs, power tied to a signal line, or reversed polarity, and it won't export a schematic with those fatal errors baked in.
• Domain kits. Circuits, ERDs, floorplans, flowcharts, and network topologies each have the right components, not generic rectangles.

And it clears the two other things that push people off CAD and off cloud tools:

• No CAD license. Full desktop CAD runs $2,000–$10,000/seat a year. This is free to use.
• No cloud upload of your IP. It runs in your browser and saves plain SVG — a file you can drop straight into a Git repo, no cloud sync, no NDA review over where your design lives.

When you'd still reach for full CAD

If you're doing manufacturing-grade PCB layout with design-rule checks for fabrication, a dedicated EE package (KiCad if you want free, Altium if you want the full suite) is the right tool. Schema Editor is for the enormous middle ground above whiteboard tools and below full CAD: real schematics, ERDs, and floorplans you need to draw correctly, share, and version — without the license or the tangle.

Draw one and see the wires behave

Open Schema Editor, drop in a couple of components, wire them, and drag one across the canvas. Watch the wires follow and re-route instead of tangling. That difference is the whole point.