Choose a technical area
How these tools are designed
Each tool should state its unit system, formula inputs and important limits. They are focused calculators for a defined task, not replacements for laboratory procedures, engineering design review or specialist software.
Example: from a lab question to an engineering check
The areas above often meet in one task. To prepare 500 mL of a 0.2 M sodium chloride solution, the molarity calculator gives 0.2 mol/L × 0.5 L × 58.44 g/mol ≈ 5.84 g of NaCl. If the solution is pumped through a 20 m hose, the pressure-loss and flow tools in the engineering section estimate the pump head needed, and the pressure converter turns the result into bar or psi for the pump datasheet.
Each step uses SI units internally. When a tool asks for a value in a different unit, it says so next to the input; converting before you type avoids the most common source of wrong answers, which is a factor-of-1,000 slip between grams and kilograms or millilitres and litres.