Unit conversion tables

One page per quantity, each with the factor between every pair of its units. Temperature is the odd one out: its scales start at different zeros, so it needs formulas rather than factors, and it says so.

• Concentration pM, nM, µM, mM, M
• Volume nL, µL, mL, L
• Mass ng, µg, mg, g, kg
• Amount of substance nmol, µmol, mmol, mol
• Pressure Pa, kPa, bar, atm, mmHg, psi, Torr
• Temperature K, °C, °F
• Temperature difference K, °C, °F
• Energy mJ, J, kJ, cal, kcal, eV, keV, MeV
• Length nm, µm, mm, cm, m
• Time ns, µs, ms, s, min, h, days, years, thousand yr, million yr, billion yr
• Resistance mΩ, Ω, kΩ, MΩ
• Electric current µA, mA, A
• Voltage mV, V, kV
• Capacitance pF, nF, µF, mF, F
• Electric charge e, pC, nC, µC, mC, C
• Area mm², cm², m²
• Frequency Hz, kHz, MHz, GHz, THz
• Speed m/s, km/h, mph, ft/s
• Force mN, N, kN, kgf
• Acceleration m/s², g
• Angle °, rad, mrad
• Power µW, mW, W, kW, MW, hp
• Torque mN·m, N·m, kN·m, lbf·ft, lbf·in, kgf·m
• Spring constant N/m, N/mm, kN/m, lbf/in
• Momentum g·m/s, kg·m/s, N·s, kg·km/h
• Intensity pW/m², nW/m², µW/m², mW/m², W/m², W/cm²
• Resistivity Ω·m, Ω·cm, µΩ·cm, Ω·mm²/m

To convert an actual number rather than read off a factor, the unit converter handles all of these and turns the result into a shareable link. The SI units and prefixes table covers the prefixes themselves.