What Is a Pipette?

What a pipette is

A pipette is a laboratory tool used to measure and transfer a precise volume of liquid from one container to another. It is one of the most frequently used pieces of equipment on any bench that handles liquid samples — reagents, buffers, cell suspensions, DNA/RNA samples, and clinical or environmental specimens all move between tubes, plates, and vials by pipette.

The problem a pipette solves is accuracy at small scale. A graduated cylinder or a free pour is accurate enough for a liter of buffer; it is not accurate enough for 50 microliters of a reagent that has to be within a few percent of a target concentration for an assay to work. A pipette is built to draw up and dispense a defined volume repeatably, with a stated tolerance, so that the volume actually delivered is close enough to the intended volume for the result to be trusted.

Why pipettes exist as a distinct category of equipment

Before adjustable pipettes became standard lab equipment, liquid volumes below a milliliter were difficult to measure and transfer consistently by hand. A pipette solves that by combining a defined mechanism — typically a plunger drawing air or liquid into a disposable tip, or a fixed glass bore — with a way to set or read the volume being moved. That combination is what lets two different people, on two different days, draw the same nominal volume and get results that agree with each other closely enough for the data to be comparable.

That reliability is what research, clinical, and quality-control work depends on: an assay, a dilution series, or a formulation is only as trustworthy as the volumes that went into it. Pipetting error is a genuine, well-recognized source of variability in lab results, which is why pipette selection, technique, and calibration are treated as a real quality-control topic rather than an incidental detail.

Main types of pipettes

“Pipette” covers several distinct tools built for different jobs. The type that comes to mind first for most people who work in a lab is the micropipette, but it is one of several:

• Micropipettes (adjustable-volume, air- or positive-displacement) — the hand-held, plunger-operated pipettes used with disposable tips for volumes roughly in the sub-microliter-to-low-milliliter range. These are what most people mean by “pipette” in a molecular biology, chemistry, or clinical lab context, and they’re sold in families covering different volume ranges rather than one universal size. See What Is a Micropipette? for the dedicated explainer, and Micropipette Types and Uses: Single-Channel vs. Multichannel for a practical breakdown of the single- vs. multichannel and air- vs. positive-displacement distinctions.
• Serological pipettes — longer, typically single-use plastic pipettes marked with graduated volume lines and used with a pipette-aid or pipettor (a separate powered or manual dispensing device) rather than an integrated plunger. They’re built for larger volumes than a micropipette handles — milliliters rather than microliters — and are common for cell culture work, media transfer, and general liquid handling on the larger end.
• Volumetric pipettes — single-volume glass (or, less often, plastic) pipettes with one calibration mark, built to deliver one specific volume as accurately as possible. Where a micropipette trades some accuracy for adjustability across a range, a volumetric pipette trades adjustability for the highest achievable accuracy at exactly one volume — the classic choice for preparing an analytical standard or a precise dilution in quantitative chemistry.
• Multichannel pipettes — micropipettes with multiple (commonly 8 or 12) tips operated by a single plunger, built to move the same volume into or out of an entire row or column of a multiwell plate in one motion. They exist specifically for plate-based work — ELISA, PCR setup, cell-based assays — where pipetting the same volume dozens of times individually would be slow and would introduce more well-to-well variability than one synchronized motion does.

These aren’t fully interchangeable: choosing the wrong category for the job (a volumetric pipette for a variable dilution series, or a micropipette for tens of milliliters of media) is less about the tool being “wrong” and more about it being poorly matched to the volume range and throughput the task actually needs.

Why calibration matters

A pipette’s accuracy is not permanent. Like any mechanical measuring instrument, the internal seals, springs, and pistons in a micropipette wear with use, and even a single-volume glass pipette can be affected by chipping or contamination. An out-of-calibration pipette can deliver a volume that’s consistently off by a small, invisible margin — invisible because nothing about using it looks or feels different, only the delivered volume has drifted.

That’s why pipettes are calibrated on a defined schedule (commonly checked gravimetrically — dispensing water and weighing it against known density — against a documented tolerance) rather than left in service indefinitely. For the general concept of what calibration is and why it’s treated as a formal, documented practice across lab equipment generally, see What Is Calibration?. For the pipette-specific version — how often to calibrate, in-house verification vs. sending pipettes to an accredited calibration service, the gravimetric method, and what to do when a pipette fails a check — see Pipette Calibration: How and When to Calibrate Lab Pipettes.

Pipette tips and consumables

Micropipettes are used with disposable tips rather than being a fully self-contained instrument, and tip choice is not incidental: tip volume range, fit (a poorly seated tip is a common source of pipetting error), filter/barrier construction for aerosol-sensitive work, and low-retention coatings for viscous or precious samples all affect both accuracy and cost per use. See Pipette Tips: Selection Guide by Application for how to match tip type to application, and how tip choice interacts with calibration validity.

Who uses pipettes, and who deals with buying and maintaining them

Day to day, pipettes are used by bench scientists, lab technicians, clinical laboratory staff, and quality-control analysts — essentially anyone whose work involves moving small, precise liquid volumes. But selecting, budgeting for, and maintaining a lab’s pipette fleet is a broader research-administration and lab-management concern:

• Lab managers typically own the calibration schedule, decide when a pipette is due for service or replacement, and track which pipettes are assigned to which bench or protocol.
• Procurement and equipment managers factor pipette and tip costs into recurring lab-supply budgets (tips in particular are a genuine ongoing consumable cost, not a one-time purchase), and evaluate calibration-service contracts and turnaround times.
• Quality assurance and compliance staff, in labs operating under ISO/IEC 17025, GLP, or similar quality frameworks, need documented calibration records for every pipette in service — an assessor will ask for that documentation, not just take an informal assurance that pipettes “get checked.”

Because pipettes are used constantly and by nearly every bench role, a lab’s pipette fleet is disproportionately consequential for both its running costs and its data-quality risk relative to how little attention any single pipette gets on its own.

Frequently asked questions

What is a pipette used for?

A pipette is used to measure and transfer a precise volume of liquid — anything from a sub-microliter reagent addition to tens of milliliters of culture media — in a way that’s repeatable enough for the result to be scientifically or analytically trustworthy.

What is the difference between a pipette and a micropipette?

A micropipette is one specific type of pipette: an adjustable-volume, plunger-operated pipette used with disposable tips, typically for sub-microliter-to-low-milliliter volumes. “Pipette” is the broader category that also includes serological pipettes, volumetric pipettes, and multichannel pipettes, each built for a different volume range or workflow.

What are the main types of pipettes?

The main categories are micropipettes (adjustable-volume, hand-held, used with disposable tips), serological pipettes (graduated, single-use, used with a separate pipettor for larger volumes), volumetric pipettes (single-volume glass pipettes built for maximum accuracy at one specific volume), and multichannel pipettes (multiple tips on one plunger, for plate-based work).

Why do pipettes need to be calibrated?

The mechanical components that control how much liquid a pipette draws and dispenses wear with use, which can shift the actual delivered volume away from the set volume without any visible sign. Calibration checks and documents whether a pipette is still within an acceptable tolerance, and it’s how a lab can show — not just assert — that its pipetting was accurate.

How accurate does a pipette need to be?

Required accuracy depends on the application: a quantitative chemistry or diagnostic assay generally demands tighter tolerance than a qualitative screening step. Rather than one universal number, labs typically set and document an acceptable tolerance per pipette or per application as part of their calibration program, informed by the pipette manufacturer’s stated specifications for that model and volume range.

For related lab-equipment coverage, see What Is Lab PPE? for the personal protective equipment considerations that apply when pipetting hazardous or biological liquids, and What Is a Centrifuge? for another core piece of liquid-handling-adjacent bench equipment.