Electrolytic capacitors

[ppppenguin]

init4fun's comment is entirely correct but misses an important point.

If a capacitor reads much higher than its marked value then you are probably using a modern tester and the capacitor is leaky. This is simply due to the way modern testers do the measurement. Effectively they charge capacitor through a resistor (or with a constant current) and measure the rate of rise of voltage. Any leakage slows down the charging and gives an erroneously high reading.

With an electrolytic this may well not matter - they all leak to some extent. With any other sort of capacitor then a high reading means it's leaky and should be changed.

A traditional capacitance bridge will give a correct reading but not many of us use them for routine measurements.