Hi Product Hunt! I’m the maker of Jisuan (即算), a macOS app built around a simple idea: calculate right where you type. When filling out a web form, switching to a calculator and copying the answer back breaks your flow. With Jisuan, type an expression in a supported Chrome text field, press ⌘⌥=, choose a result, and confirm to write it back into the same field. It handles everyday arithmetic, amounts, dates, and ratios, with Pro features for financial expressions such as tax calculations. Calculations run locally on your Mac, and results are only written back after you confirm. Jisuan is currently in public beta for Google Chrome on macOS. Core calculations are free. You can download it and find tutorials at usejisuan.com. I’d love your feedback: which calculation do you most often need while filling out a web form?

Jisuan

Jisuan — Calculate right where you type.

Jisuan — Calculate right where you type.