tldraw

tldraw builds an infinite-canvas SDK that lets developers add whiteboards, custom elements, interactions, and multiplayer collaboration to web applications. It powers the company’s free web whiteboard, ClickUp’s Whiteboards, Padlet’s Sandboxes, and Jam’s screenshot annotations. Its tldraw offline desktop application lets people diagram, annotate, and wireframe using local files; coding agents can edit those files and add persistent scripts that change canvas behavior. Introduced in 2026, the desktop app also supports LAN multiplayer, with a participant’s computer hosting the collaboration server.

London-based tldraw was founded in 2022 by Steve Ruiz, its current CEO. The company grew from his 2021 side project exploring digital ink. Its engineering work includes Signia, a reactive state library designed for large, frequently changing collections of canvas data. Signia uses logical clocks to cache derived values and change descriptions to update them incrementally, reducing the need to recompute entire collections. It also supports transactions with rollbacks.

In 2025, tldraw reported approximately $1 million in revenue from its first year of sales and said it had helped hundreds of companies prototype, develop, and ship canvas experiences. That year it raised a $10 million Series A led by Lux Capital and Definition. Its SDK business sells commercial licenses; production use requires an appropriate license key.