I built the Greenhouse Herbicide Calculator to turn field label rates into practical volumes for small greenhouse experiments.
The design follows the calculation order used at the bench: scale the recommended product rate to the greenhouse area, adjust it for the target spray volume, and then apply each experimental rate multiplier. When the required volume is too small to pipette reliably, the calculator suggests a 1/10 or 1/100 working solution. It can also calculate surfactant volume and export an Excel-compatible treatment sheet.
The tool is a single offline web page with English and Thai interfaces. It has no server, account, analytics, or external library, so experimental information remains on the device. The result is still a preparation aid rather than a substitute for checking the product label and laboratory protocol.
Project repository: Greenhouse Herbicide Calculator on GitHub
Next, I would like to build a PCR reaction mix calculator that scales Master Mix and component volumes by sample number, replicates, and extra-volume allowance.