Small tools for everyday questions

CalcOak is a collection of focused calculators and converters for the questions that come up while you are shipping a parcel, comparing prices at the store, scheduling a call across time zones or working out tax on an invoice. Each tool does one job and tries to do it properly: the shipping calculator knows the real divisors DHL, FedEx and UPS use, the business-day counter skips the public holidays of the country you pick, and the meeting planner shows working hours for every city at once.

Everything runs in your browser. There are no accounts, nothing is uploaded, and the pages stay light enough to use on a phone with a slow connection. New tools are added regularly, and each one is tested against the real formulas or standards it is based on.