Excalidraw
A free whiteboard that opens instantly with no account, which is what most remote design interviews and most design discussions actually need. Practise on the tool you will be handed rather than discovering it live.
Tool
System Design
Excalidraw
Minutes to learn
All
Free
What it is
An open source virtual whiteboard with a deliberately rough, hand drawn style, no signup, and a live collaboration mode from a shared link.
Why it belongs in a system design list
Remote design interviews happen on a shared canvas, and candidates lose real minutes fighting the tool: hunting for the arrow, failing to align boxes, redrawing something they deleted. Ten minutes of practice removes that entirely, and the difference in how composed you appear is larger than it sounds.
Beyond interviews
It is also the fastest way to think through a design with a colleague. The sketchy aesthetic is a real feature, because a diagram that looks provisional invites people to argue with it, and a polished one quietly discourages that.
Best for: rehearsing before a remote design round, and everyday architecture sketching.
Ready to start?
Opens on Excalidraw in a new tab.
Stuck on something specific?
Writing only gets you so far. If you want an answer to your situation rather than the general case, book a session and we will work through it together. Every session is free; a few slots open each week.
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