Viscosity Converter
ScienceConvert dynamic viscosity units instantly — pascal-second, centipoise, poise, and imperial units. Used in fluid mechanics, food science, and petroleum engineering.
From
To
All conversionsfor 1 Centipoise (cP)
| Pascal-second (Pa·s) | 0.001 |
| Millipascal-second (mPa·s) | 1 |
| Micropascal-second (µPa·s) | 1000 |
| Centipoise (cP) | 1 |
| Poise (P) | 0.01 |
| Decipoise (dP) | 0.1 |
| Kilogram/metre·second (kg/m·s) | 0.001 |
| kgf·s/m² | 0.00010197162 |
| lbf·s/ft² | 0.000020885434 |
| lb/ft·s (slug/ft·s equiv.) | 0.00067196895 |
What is a Viscosity?
A Viscosity Converter translates dynamic viscosity measurements between SI, CGS, and imperial units. Dynamic viscosity quantifies a fluid's internal resistance to flow — the force required to move one layer of fluid over another. It appears in fluid mechanics, chemical engineering, petroleum processing, food science, and pharmaceutical manufacturing.
The SI unit is the pascal-second (Pa·s), but the centipoise (cP) remains the most widely used unit in practice because water at 20°C has a viscosity of approximately 1 cP — making it a convenient reference. The relationship is simple: 1 cP = 1 mPa·s = 0.001 Pa·s.
The converter covers 10 units across SI, CGS, and imperial systems:
- SI: Pa·s, mPa·s, µPa·s
- CGS: centipoise (cP), poise (P), decipoise (dP)
- Technical metric: kgf·s/m² (older European standards)
- Imperial: lbf·s/ft², lb/ft·s
For density-related conversions used alongside viscosity in fluid characterisation, see the Density Converter. For flow rate conversions, see the Flow Converter.
How to use this Viscosity calculator
- Enter the viscosity value in the From field.
- Select the From unit (e.g. centipoise, cP).
- Select the To unit (e.g. Pa·s, pascal-second).
- The converted value appears instantly.
- Use the reference table to see all unit equivalents at once.
- Click ⇄ to reverse the conversion.
Formula & Methodology
Base unit: Pascal-second (Pa·s)
Conversion: Result = Input × (toBase_from ÷ toBase_to)
| Unit | Pa·s equivalent |
|---|---|
| Pa·s | 1 |
| mPa·s (= cP) | 0.001 |
| µPa·s | 0.000001 |
| cP | 0.001 |
| P (poise) | 0.1 |
| kgf·s/m² | 9.80665 |
| lbf·s/ft² | 47.88026 |
| lb/ft·s | 1.488164 |
Worked example: Convert 500 cP to Pa·s.
- 500 × 0.001 = 0.5 Pa·s
Common reference viscosities:
| Fluid | Approx. viscosity |
|---|---|
| Air | 0.018 cP |
| Water (20°C) | 1 cP |
| Milk | 2–3 cP |
| Vegetable oil | 50–100 cP |
| Honey | 2,000–10,000 cP |
| Glycerol | ~1,500 cP |Frequently Asked Questions
What is dynamic viscosity?
Dynamic viscosity (also called absolute viscosity) measures a fluid's resistance to flow when a shear stress is applied. It is the ratio of shear stress to shear rate and is expressed in pascal-seconds (Pa·s) in SI units. Honey has a much higher dynamic viscosity than water — it flows slowly because its internal resistance to deformation is high.
What is the difference between dynamic and kinematic viscosity?
Dynamic viscosity (η) measures resistance to flow under an applied force, expressed in Pa·s or centipoise. Kinematic viscosity (ν) is dynamic viscosity divided by density, expressed in m²/s or centistokes (cSt). Kinematic viscosity is used in applications where gravity drives the flow (lubricants, fuels), while dynamic viscosity is used in forced-flow applications (pumps, injection moulding).
What is a centipoise and how does it relate to Pa·s?
A centipoise (cP) is 1/100 of a poise (P), a CGS unit of dynamic viscosity. 1 cP = 1 mPa·s (millipascal-second). Water at 20°C has a dynamic viscosity of approximately 1 cP (1 mPa·s), which makes centipoise a convenient everyday reference — a fluid with 10 cP is ten times more viscous than water.
What are the viscosities of common fluids?
At room temperature: water ≈ 1 cP, vegetable oil ≈ 50–100 cP, honey ≈ 2,000–10,000 cP, glycerol ≈ 1,500 cP, engine oil (SAE 30) ≈ 100–200 cP, air ≈ 0.018 cP. These reference values help contextualise a measurement — 5 cP means roughly five times the flow resistance of water.
What unit does Indian petroleum engineering use?
Petroleum engineers in India and internationally use centipoise (cP) for reservoir fluid viscosity and millipascal-second (mPa·s) interchangeably. Crude oil viscosity in Indian basins (Bombay High, Rajasthan) typically ranges from 1–10 cP for light crude to several thousand cP for heavy crude. Drilling mud rheology is also measured in cP.
What is a poise?
A poise (P) is the CGS unit of dynamic viscosity, defined as one dyne-second per square centimetre (dyn·s/cm²). It equals 0.1 Pa·s. The centipoise (cP) is 100 times smaller and more convenient for everyday fluids. Water at 20°C is approximately 0.01 P (1 cP).
When is lbf·s/ft² used?
Pounds-force second per square foot (lbf·s/ft²) is the imperial unit of dynamic viscosity, sometimes called the 'reyn' informally in lubrication engineering. It is used in US aerospace and mechanical engineering when working in the imperial foot-pound-second system. 1 lbf·s/ft² = 47.88 Pa·s.
Can I convert between dynamic and kinematic viscosity here?
No — this converter handles dynamic viscosity only. To convert to kinematic viscosity, you also need the fluid's density. Kinematic viscosity (ν) = dynamic viscosity (η) ÷ density (ρ). Use the [Density Converter](/density-converter/) to work with density values.
What is viscosity used for in food science?
Food manufacturers measure viscosity to control product texture, mouthfeel, and processing behaviour. Sauces, creams, and beverages are characterised by viscosity in centipoise or millipascal-seconds. Quality control labs use viscometers to ensure batch consistency — a sauce thicker than 800 cP may not flow correctly through a filling line.
What does kgf·s/m² mean?
Kilogram-force second per square metre (kgf·s/m²) is a technical metric unit of dynamic viscosity. It is not part of SI but appears in older European engineering standards. 1 kgf·s/m² = 9.80665 Pa·s (because 1 kgf = 9.80665 N). It is occasionally encountered in hydraulic engineering specifications from the mid-20th century.