sheetjs_sheetjs/docbits/64_cellprops.md

Hyperlinks

Hyperlinks are stored in the l key of cell objects. The Target field of the hyperlink object is the target of the link, including the URI fragment. Tooltips are stored in the Tooltip field and are displayed when you move your mouse over the text.

For example, the following snippet creates a link from cell A3 to https://sheetjs.com with the tip "Find us @ SheetJS.com!":

ws['A3'].l = { Target:"https://sheetjs.com", Tooltip:"Find us @ SheetJS.com!" };

Note that Excel does not automatically style hyperlinks -- they will generally be displayed as normal text.

Links where the target is a cell or range or defined name in the same workbook ("Internal Links") are marked with a leading hash character:

ws['A2'].l = { Target:"#E2" }; /* link to cell E2 */