Kinematic viscosity converter
Convert kinematic viscosity between m²/s, stokes, centistokes and ft²/s and see all four at once: 1 m²/s equals 10000 stokes or 1000000 centistokes. For oil grade sheets, hydraulics homework and lab reports. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Amount
- 1
- Input kinematic viscosity unit
- m2_s
- Output kinematic viscosity unit
- centistokes
- Result
- 1,000,000
- M2 per s
- 1
- Stokes
- 10,000
- Centistokes
- 1,000,000
Kinematic viscosity conversion between SI square meters per second, CGS stokes and centistokes, and imperial square feet per second is a daily chore in lubrication engineering, petroleum product specs, hydraulics homework, and fluid-mechanics lab reports. People search for a kinematic viscosity converter when they need water-like one square millimeter per second next to one centistoke, or a process-fluid reading in m²/s next to ft²/s for an imperial datasheet, not a general multi-unit toolbox that also handles length and temperature. This capability accepts one finite amount plus from and to unit labels among m²/s, stokes, centistokes, and ft²/s, bridges every conversion through square meters per second so results stay consistent, and returns the target value together with the same viscosity expressed in all four units. Unrecognized unit names are rejected with a clear validation error instead of silently guessing a nearby symbol.
How the kinematic viscosity converter maps SI, CGS and imperial units through m²/s
Start from the square meter per second as the SI coherent unit of kinematic viscosity and express every other unit as a fixed factor into m²/s. One stokes equals exactly one square centimeter per second, which is ten to the minus four square meters per second by the exact CGS-to-SI length scale. One centistokes is one hundredth of a stokes and therefore exactly ten to the minus six square meters per second, which is also one square millimeter per second—the number printed on nearly every oil and coolant grade sheet.
The international foot is defined as exactly zero point three zero four eight meters, so one square foot is zero point three zero four eight squared square meters, giving the exact ft²/s factor into m²/s used here. This calculator never mixes those paths ad hoc. It multiplies the input amount by the factor of the source unit to reach m²/s, then divides by the factor of the target unit to produce the result.
Because every path shares the same intermediate, converting one centistokes to m²/s and back, or comparing stokes to square feet per second, stays numerically consistent within ordinary floating-point precision. The tool does not convert dynamic viscosity in pascal-seconds or poise, does not apply temperature-dependent oil charts, does not map SAE grades to viscosity without a grade table, and does not fetch live fluid databases.
It answers only the algebraic kinematic viscosity unit conversion people mean when they type kinematic viscosity converter into a search bar and expect m²/s, stokes, centistokes, and ft²/s.
Where dedicated kinematic viscosity conversion shows up in real work
Secondary-school and college fluid-mechanics courses constantly assign problems that give a fluid viscosity on one scale and ask for another, often mixing lab-style centistokes with SI m²/s and imperial ft²/s in the same worksheet. Lubrication and petroleum engineers report base-oil and hydraulic-fluid grades in centistokes at standard temperatures while design tools and SI-native CFD models expect square meters per second, so a single conversion pass keeps lab certificates, data sheets, and sensors aligned.
HVAC and process piping teams normalize coolant and fuel kinematic viscosity fields between metric datasheets and United States industrial specs before Reynolds-number checks. Laboratory and quality-control workflows step between cSt for viscometer readouts and m²/s for report templates without reimplementing factors in every spreadsheet. If you later need dynamic viscosity conversion, density conversion, or temperature scales, treat those as separate search intents and landings rather than overloading this kinematic viscosity converter page.
What you can do with it
Oil and lubricant grade sheets
Normalize centistokes lab readouts to m²/s for SI reports and CFD models without hand-written factors.
Fluid-mechanics homework and Reynolds checks
Convert m²/s, stokes, and ft²/s so textbook problems and pipe-flow calculators share one ground truth.
FAQ
What happens if I send an unrecognized unit?
The error message includes Unrecognized unit and lists the supported families so you can correct the label.
How does 1 centistokes relate to m²/s?
Exactly 10⁻⁶ m²/s. One centistokes is also exactly 1 mm²/s and one hundredth of a stokes.
Does this convert dynamic viscosity (Pa·s or cP)?
No. Kinematic viscosity is ν = η/ρ (m²/s family). Dynamic viscosity in pascal-seconds or centipoise is a different quantity and a different landing.
What does it cost?
The browser tool is free and runs locally.
Can it turn an SAE oil grade into a viscosity value?
No. It only converts between viscosity units. An SAE grade or a temperature chart needs the oil's own grade table, which this converter does not apply or look up.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/conv/kinematic-viscosity \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"amount":1,"from":"m2_s","to":"centistokes"}'const res = await fetch("https://api.kit.forhosting.com/conv/kinematic-viscosity", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"amount": 1,
"from": "m2_s",
"to": "centistokes"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/kinematic-viscosity",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"amount": 1,
"from": "m2_s",
"to": "centistokes"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/kinematic-viscosity", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"amount":1,"from":"m2_s","to":"centistokes"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"amount":1,"from":"m2_s","to":"centistokes"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/kinematic-viscosity", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"amount": 1,
"from": "m2_s",
"to": "centistokes"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.kinematic_viscosity",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
What you send and what you get back from the API and browser form
Send three fields: amount, a finite number for the kinematic viscosity magnitude; from, a string naming the input unit; and to, a string naming the output unit. When a unit string is unknown the error message includes Unrecognized unit and lists the four supported families so clients can fix the label rather than guessing. Classic checks include one square meter per second becoming ten thousand stokes or one million centistokes, one centistokes equaling exactly one times ten to the minus six m²/s, and one square foot per second equaling zero point zero nine two nine zero three zero four m²/s. Both unit fields accept short keys and everyday words in any common casing, including m2_s or m2/s or square meters per second, stokes or St or cm2/s, centistokes or cSt or mm2/s, and ft2_s or ft2/s or square feet per second. Missing fields, non-numeric amount strings, NaN, Infinity, and unrecognized unit labels fail with invalid_input and are not charged. On success the response echoes the cleaned amount, normalized from and to keys, the primary result in the target unit, the same viscosity as m2_per_s, stokes, centistokes, and ft2_per_s with twelve significant digits of stable precision, the SI factors used, the formula string, and method m2_s_bridge. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.
Where dedicated kinematic viscosity conversion shows up in real work
Data pipelines that ingest mixed IoT or LIMS payloads with cSt, St, and m2/s tags can call this capability once per reading instead of reimplementing the factors in every service. Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance.
Integration use cases
Process tags and LIMS pipelines
Map mixed St, cSt, and mm²/s sensor tags to a single SI field for quality dashboards and regression fixtures.
Technical questions
Which kinematic viscosity units does this converter support?
Square meters per second (m2_s), stokes (St), centistokes (cSt), and square feet per second (ft2_s). Common aliases such as mm2/s, cm2/s, and sq ft/s are accepted; the response normalizes to short keys.