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Viscosity Converter

Dynamic viscosity measures a fluid resistance to flow. The metric unit is the pascal second, and industry mostly uses the centipoise, where one centipoise equals one millipascal second and 1,000 centipoise equals one pascal second. Water at room temperature is about one centipoise.

Decimals
Pascal seconds
1Pa·s

For reference: water at room temperature is about 1 cP, olive oil around 80 cP, and honey roughly 10,000 cP.

Common values
CentipoisePascal secondsPoise
1 cP0.001 Pa·s0.01 P
10 cP0.01 Pa·s0.1 P
100 cP0.1 Pa·s1 P
1000 cP1 Pa·s10 P
10000 cP10 Pa·s100 P
100000 cP100 Pa·s1000 P

How to convert viscosity units

  1. Pick the two units

    Choose the unit on your data sheet and the unit your calculation needs.

  2. Enter the value

    Type into either field and the other converts live, in whichever direction you need.

  3. Sanity-check against a fluid

    Compare the result to water, oil or honey using the note and the reference table.

  4. Copy the result

    Copy the converted value into your spec or calculation.

Why use this tool

The units data sheets actually use

Centipoise and millipascal seconds sit alongside pascal seconds and poise, plus the two imperial forms that appear in older references.

Both directions in one pair

Edit either field and the other follows, so there is no mode to switch and no factor to remember.

Common fluids for scale

Water, olive oil and honey are quoted next to the result, which is the fastest way to catch a factor-of-ten mistake.

Dynamic viscosity only, on purpose

Kinematic units are excluded because converting to them requires the density of your specific fluid.

Runs entirely in your browser

Nothing you type is uploaded or stored.

About this tool

Dynamic viscosity, sometimes called absolute viscosity, measures how strongly a fluid resists flowing. The metric unit is the pascal second, but almost nobody quotes it that way in practice. Industry data sheets overwhelmingly use the centipoise, partly because water at room temperature comes out at almost exactly 1 cP, which makes every other fluid easy to place mentally. One centipoise is one millipascal second, and 1,000 centipoise make a pascal second.

The poise itself comes from the older centimetre-gram-second system and equals 0.1 pascal seconds. Imperial engineering references sometimes use pound-force seconds per square foot, which is a very large unit at 47.88 pascal seconds, or pounds per foot second at 1.488 pascal seconds. All of these measure the same quantity, so each is a fixed multiple of the others and converts cleanly in either direction.

What this tool deliberately does not do is convert to kinematic viscosity, the unit family that includes stokes, centistokes and square metres per second. Kinematic viscosity is dynamic viscosity divided by the fluid density, so relating the two requires knowing exactly which fluid you have and at what temperature. A converter that offered both lists side by side would be quietly assuming a density. For related work there is the density converter, the flow rate converter, and the general unit converter.

Frequently asked questions

How do I convert centipoise to pascal seconds?
Divide by 1,000. A fluid at 1,000 cP is 1 Pa·s, and 80 cP is 0.08 Pa·s. Centipoise and millipascal seconds are the same size, so 80 cP is also 80 mPa·s.
What is the viscosity of water?
About 1 centipoise at 20°C, which is 0.001 pascal seconds. That near-exact match is why centipoise became the everyday unit: it makes water the natural reference point.
Why can I not convert to centistokes here?
Centistokes measure kinematic viscosity, which is dynamic viscosity divided by density. Converting between the two families needs the density of your specific fluid at your specific temperature, so it cannot be done from the viscosity value alone.
Is centipoise the same as millipascal second?
Yes, exactly. One centipoise equals one millipascal second, so a value quoted in either unit can be read straight across without converting.
Does viscosity change with temperature?
Considerably, and for liquids it falls as temperature rises. A viscosity figure is only meaningful alongside the temperature it was measured at, which is why data sheets always state both.
Is my data uploaded anywhere?
No. The conversion runs in your browser and nothing you type leaves your device.

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