Burette vs Pipette: Which to Use and Why It Matters for Accuracy

Burette vs Pipette: Which to Use and Why It Matters for Accuracy

Pick by the job, not by habit

Burette vs pipette, side by side

Standards

Frequently asked questions

IntroShort answer: use a burette when you need to deliver a variable volume with drop-by-drop control (titrations, finding an endpoint). Use a pipette when you need to transfer a fixed volume repeatably (standards, aliquots, reagent addition). A burette cannot replace a pipette — they do different jobs.

  • SituationTitration / find an endpoint
    RecommendBurette
    ReasonDropwise control; read any delivered volume
  • SituationDeliver one fixed volume (standards, aliquots)
    RecommendVolumetric (bulb) pipette
    ReasonSingle calibration mark, tightest tolerance
  • SituationSeveral small volumes, speed over top accuracy
    RecommendGraduated / serological pipette
    ReasonScaled and flexible, lower precision
  • SituationSub-millilitre work (DNA, enzymes, assays)
    RecommendMicropipette
    ReasonMicrolitre range; tip is part of the system
  • SituationApproximate, non-critical volume
    RecommendGraduated cylinder
    ReasonFast; not for quantitative results

  • ParamVolume type
    ColAVariable, 0 to full capacity
    ColBFixed (volumetric) or small range (graduated)
  • ParamControl
    ColAStopcock, dropwise
    ColBSuction/plunger, one transfer
  • ParamTypical use
    ColATitration, quantitative analysis
    ColBAliquots, standards, reagent transfer
  • ParamClass A tolerance
    ColAAbout +/-0.05 mL, 50 mL (ISO 385)
    ColBSingle fixed volume, tight tolerance (ISO 648)
  • ParamBest accuracy at
    ColAFull / interpolated readings
    ColBExactly its rated volume
  • ParamReading
    ColAMeniscus, interpolate to ~0.05 mL
    ColBTo the calibration mark

Body

TD vs TC — the detail that quietly ruins results

Glassware is calibrated one of two ways. TD (To Deliver / “Ex”) accounts for the film left behind: the residual in the tip is expected and must not be blown out. TC (To Contain / “In”) holds the stated volume and must be rinsed or blown out to deliver it all. Using a TD pipette as if it were TC over-delivers every single time — check the TD/TC marking before you trust the volume.

“Most accurate” depends on volume, not on the tool

A burette and a volumetric pipette are comparably precise at full capacity; the volumetric pipette is usually called more accurate only because it is not meant to be used at partial volumes. A burette loses relative accuracy on very small deliveries. So “which is more accurate” has no answer without naming the volume.

Three mistakes that cost accuracy

  1. Not rinsing the burette with the titrant first — leftover water dilutes it.
  2. Treating the tip as separate from calibration — under ISO 8655-2 the pipette and tip are one system; changing tip type requires recalibration.
  3. Reading the meniscus off eye-level (parallax error).

  • LabelISO 385
    ValueBurettes (accuracy classes A/B)
  • LabelISO 648
    ValueVolumetric (one-mark) pipettes
  • LabelISO 8655:2022
    ValuePiston-operated pipettes; tip-as-system

  • Is a pipette more accurate than a burette?
    Only at a fixed volume. At variable volumes the burette wins on control.
  • Can a burette replace a pipette?
    No — different jobs: titration versus fixed-volume transfer.
  • What does TD / Ex mean on a pipette?
    To Deliver: the residual film in the tip is expected — do not blow it out.

CTANot sure which pipette? See the full guide to types of pipettes.