Hissab is a strict, unit-aware natural-language calculator. Type real-world math - units, dates, finance, percentages, IP/CIDR, matrices, symbolic algebra and get exact, auditable answers. One engine runs across the web/PWA app, Chrome extension, CLI, embeddable npm library, and hosted MCP server that AI agents can call instead of guessing. Now open-source.

Hissab is a text based calculator app that does way more than calculations. Hissab is useful for performing quick calculations as well as complex workflows. Hissab can do unit and currency conversions, date, time & timezone operations and so much more.