A Volumetric pipette is a tool for measuring accurate volumes of a liquid. Pipettes are typically long tubes, open on both ends, marked to contain (or deliver) a certain volume of liquid.
They are commonly used in analytical chemistry to make up diluted solutions by measuring out a known volume of the concentrated stock solution, or to measure out a known volume of a solution to be titrated.
Volumetric pipettes are typically calibrated for only one volume (e.g., 5.00 mL). Many different sizes are available.
ASTM standard E969 defines the standard tolerance for volumetric transfer pipettes. The tolerance depends on the size: a 0.5-mL pipette has a tolerance of ±0.006 mL, while a 50-mL pipette has a tolerance of ±0.05 mL. (These are for Class A pipettes; Class B pipettes are given a tolerance of twice that for the corresponding Class A.)
A specialized example of a volumetric pipette is the microfluid pipette (capable of dispensing as little as 10µL) designed with a circulating liquid tip that generates a self-confining volume in front of its outlet channels.