Pipette Guide: Types, Techniques, and How to Choose the Right One

A pipette transfers a measured volume of liquid from one vessel to another. Which type you need depends on three things: the volume range, the liquid properties, and how much accuracy the application requires. This guide covers every common pipette type, the two core techniques (forward and reverse), and the decisions that determine accuracy in practice.

Pick by the job, not by habit

  • 0.1–1000 µL, standard bench work
    Single-channel micropipette (P10/P200/P1000)
    Most common lab pipette; choose the smallest that covers your volume
  • Loading 96-well or 384-well plates
    8- or 12-channel micropipette
    Parallel dispensing; saves time and reduces row-to-row variation
  • 1–25 mL, general transfer
    Serological or graduated pipette
    Larger volumes; flexible scale for variable amounts
  • One precise fixed volume (standards, references)
    Volumetric (one-mark) pipette
    Single calibration mark = tightest tolerance at one specific volume
  • Titration / variable volume with drop control
    Burette
    Stopcock gives continuous dropwise delivery; read any volume on scale
  • Viscous, volatile, or foaming liquids
    Reverse pipetting technique
    Forward technique mis-delivers on difficult liquids; reverse compensates

Burette vs pipette, side by side

  • Volume range
    0.1–1000 µL (across P2–P1000)
    1–25 mL
  • Volume flexibility
    Fixed models per range
    Continuous scale within range
  • Accuracy class
    ISO 8655 Class A/B
    ISO 835 / manufacturer spec
  • Liquid control
    Plunger; precise stop points
    Pipette aid / filler; flow by suction
  • Typical use
    Molecular biology, PCR, cell culture
    Media, reagents, general transfer
  • Tip system
    Disposable tip (part of calibration)
    Sterile plugged tip or cotton-plugged

The one rule that improves every pipetting result

Use the smallest pipette that comfortably covers your volume. Accuracy is best in the top third of a pipette's range and worst near the bottom. A P1000 set to 100 µL operates at 10 % of its range — where tolerance is at its worst. A P200 set to 100 µL operates at 50 % — far more accurate. Same volume, same brand, measurably different result. This single rule eliminates more pipetting error than any technique refinement.

Forward vs reverse — choose by the liquid, not by habit

Forward pipetting (press to first stop, aspirate, dispense to first stop) is correct for aqueous solutions. Reverse pipetting (press to second stop, aspirate overage, dispense to first stop only) is correct for viscous, volatile, or foaming liquids. Using forward technique on glycerol or DMSO causes systematic under-delivery. Using reverse on water is harmless but unnecessary. The liquid decides the technique.

The tip is part of the calibrated system

Under ISO 8655, a piston-operated pipette and its tip are calibrated together as one unit. Changing tip brand or type changes the air-cushion geometry and can shift accuracy outside Class A limits — without the pipette itself changing at all. Pre-wet the tip before the first real draw (aspirate and expel once), and recalibrate after any tip-type change that will be used for critical work.

Standards

  • ISO 8655:2022
    Piston-operated volumetric apparatus (micropipettes); tip + pipette as one system
  • ISO 835:2007
    Graduated pipettes — capacity, graduation, and tolerance classes
  • ISO 648:2008
    One-mark volumetric pipettes — Class A and Class B tolerance limits

Frequently asked questions

  • What is a pipette used for?
    Transferring a measured volume of liquid between vessels — from sub-microlitre PCR work to 25 mL media transfers. The type of pipette determines the volume range and accuracy.
  • How do I choose the right pipette?
    Match the pipette range to your volume (use the smallest that covers it), match the technique to the liquid (forward for aqueous, reverse for viscous/volatile), and verify the tip is the correct type for the pipette.
  • What is the difference between forward and reverse pipetting?
    Forward: aspirate to first stop, dispense to first stop — for aqueous liquids. Reverse: aspirate to second stop (overage), dispense to first stop only — for viscous, volatile, or foaming liquids.
  • How often should pipettes be calibrated?
    Every 3–12 months as a baseline; high-throughput labs should calibrate more frequently. Recalibrate after any tip-type change used for critical or regulated work.
Need pipettes or tips for your lab at scale? Contact us for factory-direct supply from ISO-certified manufacturers.