A pipette (sometimes spelled as pipet) is a type of laboratory tool commonly used in chemistry and biology to transport a measured volume of liquid, often as a media dispenser. Pipettes come in several designs for various purposes with differing levels of accuracy and precision, from single piece glass pipettes to more complex adjustable or electronic pipettes. Many pipette types work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense liquid. Measurement accuracy varies greatly depending on the instrument.

The first simple pipettes were made of glass, such as Pasteur pipettes. Large pipettes continue to be made of glass; others are made of squeezable plastic for situations where an exact volume is not required.

During or prior to 1877, Joseph Lister (1827 – 1912) invented the first adjustable micropipette, consisting of a "pipette with a syringe" (photograph shown at right).

"...by means of this little syringe with a graduated disc and a piston rod in the form of a screw, graduated 2-100ths of a minim, by which means you can, with perfect precision, unit 1-100th of a minim, or 2-100ths, or any number you choose."

The micropipette was patented in 1957 by Dr Heinrich Schnitger (Marburg, Germany). The founder of the company Eppendorf, Dr. Heinrich Netheler, inherited the rights and started the commercial production of micropipettes in 1961.

The modern adjustable micropipette is a Wisconsin invention developed through interactions among several people, primarily inventor Warren Gilson and Henry Lardy, a professor of biochemistry at the University of Wisconsin–Madison.

Although specific names exist for each type of pipette, in practice, any type can be referred to as a "pipette". Pipettes that dispense less than 1000 μL are sometimes distinguished as micropipettes.

The terms "pipette" and "pipet" are used interchangeably despite minor historical differences in their usage.