A method for managing a dynamically-sized chunked spreadsheet model on a server includes creating, on the server, a plurality of chunks representing a spreadsheet, where a first chunk in the plurality of chunks includes a first range of cells in the spreadsheet. The method further includes storing on the server a mutation log for the spreadsheet, and receiving a first plurality of mutations from a plurality of client computers, where the first plurality of mutations are stored in the mutation log. The method further includes applying the first plurality of mutations to the first chunk in response to a first client computer in the plurality of client computers requesting the first range of cells, and sending the first chunk to the first client computer.