What it does
NapkinBook presents a whiteboard designed to compute a forecast rather than merely display shapes. Its field guide describes connecting data sources and operations to charts and uncertainty values on one canvas, with sharing and presentation modes. The homepage says users can try it free and sign in to save and sync; it also describes encrypted live collaboration.
NapkinBook is a specialized canvas for making assumptions and their consequences visible. Connecting inputs, operations, and charts can help a group inspect how a forecast changes instead of passing numbers between spreadsheets and slides. The product’s storage wording is not fully consistent: the homepage describes account-backed saving and sync, while the field guide describes boards as local until exported or shared. The retrieved pricing text did not establish a paid plan or the free-trial duration.
Strengths
- The canvas links data sources, calculations, charts, and uncertainty values.
- The product supports live collaboration and presentation-style walkthroughs.
Watch out for
- The storage and sync description differs between homepage and field guide.
Best for
- Analysts and teams building shared, inspectable forecasts or scenario models
Sources
- NapkinBook: a computional whiteboard (Oct 25, 2026)
- NapkinBook field guide (Oct 25, 2026)