14. The system of claim 10 , wherein the view is programmed to render the model to a document object model (DOM) for the web browser.
10. A computer-implemented web browser-based document editing system, comprising: a first rich text model on a client computing device for storing a format for a rich document having text and formatting definitions for the text; a view programmed to render the model for display to an editing surface that displays the rich document; a controller to intercept and interpret inputs made by a user with respect to the document in the view and to cause the rich text model to be revised in accordance with the user inputs; and an off-screen browser display area that is not visible to a user of the browser, wherein the view is programmed to: render characters entered by a user to the off-screen browser display area; and determine dimensions for displaying the characters with the view by measuring a size of the off-screen display area.