Science & Engineering

Ohm's Law, Molar Mass, Dilution, Decibel and more

Ohm's Law Calculator

Enter any two of voltage, current, and resistance to instantly calculate the third value plus power. A free Ohm’s Law calculator based on V=IR for electronics.

Molar Mass Calculator

Enter a chemical formula to instantly calculate its molar mass. View elemental composition and mass percentages with this free online molar mass calculator.

Dilution Calculator

Free online dilution calculator. Use the C1V1=C2V2 formula to instantly find the volume, final concentration, and water to add. This solution dilution calculator handles molarity, serial dilution, and stock prep — no signup, instant results.

Decibel Calculator

Easily calculate and convert decibel (dB) values. Compare noise levels and convert power or voltage ratios to dB with this free online decibel calculator.

Parallel Resistance

Instantly calculate the total resistance of resistors connected in parallel. Enter 2 to 10 resistor values with this free online parallel resistance calculator.

LED Resistor Calculator

Calculate the correct resistor value for your LED circuit. Enter supply voltage, LED forward voltage, and current to find the ideal resistor with this free online calculator.

Wavelength-Frequency Converter

Convert between wavelength and frequency instantly. Calculate the wavelength, frequency, and energy of light, sound, and radio waves. Free online wavelength-frequency converter.

pH Calculator

Convert between hydrogen ion concentration, pH, and pOH values. Accurately calculate the pH of acid and base solutions with this free online pH calculator.