Process Tools is a provider of free online engineering calculators designed to support chemical process design and related engineering work. Its collection covers separation, reaction engineering, heat transfer, fluid mechanics, process control, and general-purpose calculations, with tools for both equipment sizing and process analysis.

Separation resources include distillation, vapor-liquid equilibrium, flash calculations, absorption, liquid extraction, crystallization, and several chromatography simulators. Reaction tools support reactor design and batch reactor simulation. For thermal applications, users can calculate heat exchanger performance, fired heater duty, evaporator design, cooling tower parameters, steam properties, and psychrometric conditions. Fluid mechanics tools address pipe flow, pumps, compressors, two-phase flow, agitators, cyclones, and orifice meters.

Process Tools also offers PID tuning, tank level control, control valve and relief valve sizing, unit conversion, and material balance calculations. Users can create simple process flow diagrams and evaluate project economics through NPV, IRR, payback, and equipment cost estimation. The site presents these calculators as free engineering resources and provides privacy, terms of service, and contact information.