Viscometers for Accurate Viscosity Measurement

Viscometers that Simplify Viscosity Measurements

Our viscometers have redefined the way viscosity is measured with the benefit of VROC^® technology. All RheoSense viscometers require only small sample volume, control from low to very high shear rates, and measure true viscosity of Newtonian and non-Newtonian liquids. Select your viscometer! Let's dig into the details.

What is the best viscometer for you?

Each type of viscometer has strengths, this quick summary and table will help you determine which option will give you the best results for your sample and application.

There are many different ways to measure viscosity. To determine which will work for you, look at your sample. Do you have a lot of sample and can spare a lot to test viscosity? Is your sample Newtonian or non-Newtonian? Does your sample need to be tested at a specific temperature?

Once you have determined those answers, look at your testing capabilities. Do you have limited time to test and clean your viscometer? Do you need to run many tests in the same day? Will the person operating the viscometer be a trained technician?

The table below provides an overview of these factors with the most common viscometer types.

Type of Viscometer	Minimum Sample Volume	Estimated Viscosity range	Can it Test Non-Newtonian Samples?	How Much Time Does it Take to Test?	How Time-Consuming is it to Clean?	User Variability	Temperature Control
Capillary (U-tube) Ostwald, Ubbelohde, Cannon-Fenske	~2–10 mL	~0.3–100,000 cSt	Newtonian samples only	20–40 min total: 10–20 min thermal equilibration + 3–15 min flow time; duplicate runs required	Time consuming cleaning protocols needed	Manual timing and equilibration introduce operator-to-operator variation	External water bath required; viscosity shifts 3–9%/°C; ±0.01 °C needed for high accuracy. Water baths are costly and time-consuming to use.
Rotational (spindle) Brookfield, coaxial cylinder	~200 mL with open beaker	~10–2,000,000 cP; spindle- and model-dependent	Variable speeds enable some shear-rate profiling Cannot specify specific shear rates	~1–5 min per reading	Basic spindle viscometers are easily cleaned. Add-ons for higher accuracy or lower sample sizes can be difficult to clean and prone to clogging.	Spindle and speed selection varies by user; open beaker has no built-in temp control.	Optional jacketed vessel or external bath; often used without temp control in QC. Lack of temperature control reduces accuracy.
Cone and plate	<1 mL (typically 0.5–0.7 mL)	~1–100,000 cP; depending on the specific model's geometry.	Uniform shear rate across full sample. Allows for one shear rate per test.	~2–10 min with significant improvement in speed for automated models.	The narrow cone–plate gap must be carefully wiped after each sample.	Automated models help to reduce human error. However, proper cone alignment must be verified manually.	Built-in Peltier element available for some models Typically 0–100 °C at ±0.1 °C.
Falling ball Höppler principle	~10–20 mL to fill tube	~0.5–100,000 mPa·s ball/tube-dependent	Limited to transparent Newtonian fluids.	~5–15 min Automated inductive sensors speed up the process.	Non-automated models are simple to clean and low maintenance.	Manual timing in basic models. Automated sensors eliminate user to user variation.	Jacketed tube with external thermostat work with standard models. Peltier is available for some automated models. Fluid density must be known to accurately test at temp.
Vibrational (oscillating)	~10 mL and up; probe dips into any vessel	~0.1–10,000 cP	Reduced accuracy for non-Newtonian fluids.	<1 min	Minimal cleaning required.	Single probe immersion handheld models are highly consistent between users.	No temperature control options.
Stabinger	~1–3 mL	~0.2–30,000 mPa·s	Best for Newtonian	~2–5 min with automated filling.	Most models include an automated solvent flush.	Automated operation removes key opportunities for operator variation.	Integrated Peltier; wide range (e.g. −40 to 135 °C)
Microfluidic chip Pressure-drop / flow-rate methods	~10–400 µL; some designs as low as ~15 µL	~1–600 cP typical; shear rates 3–1,400,000 s⁻¹ achievable	Highly accurate wih non-Newtonian fluids. Can test a variety of shear rates with one run.	Seconds to a few minutes per measurement. High-throughput automated platforms can run 96-well plates.	Chip channels require solvent flushing. Disposable options are available for some models eliminating cleaning.	Automated flow control and pressure sensing; minimal manual steps; results highly reproducible between users when chip is properly loaded.	Active temperature control (Peltier chip or external heater block) available on integrated platforms; range typically 4–70 °C. Some models require careful pre-conditioning of fluid and chip.
Rectangular slit VROC® / USP <914> Method I	15–100 µL depending on model.	~0.2–20,000 cP (chip-dependent); shear rates up to 1,400,000 s⁻¹ on high-shear models.	Defined, controllable shear rate and direct measurement of shear stress from pressure drop. Provides first principle viscosity measurements.	~1–5 min per data point. Automated and semi-automated models can run multi-temperature, multi-shear-rate sweeps unattended.	Chips must be cleaned between immiscible runs (miscible samples can be tested continuously). Automated cleaning available with built-in or external chip cleaning station.	Automated syringe pump controls flow rate precisely; software-guided protocols minimize user steps; accuracy ±2%, repeatability ±0.5% of reading.	Integrated Peltier with feedback control. 4–70 °C range typical with extended range available on some models.

Our Products

Viscometers that Simplify Viscosity Measurements

Need Help Deciding?

Our Products

What is the best viscometer for you?

Each type of viscometer has strengths, this quick summary and table will help you determine which option will give you the best results for your sample and application.

Don't Forget Your Viscometer Supplies!