Venturi Meter Flow Calculator
Flow rate through a venturi from inlet/throat diameters and measured pressure drop.
Venturis recover most of the differential pressure (low permanent loss), which is why they beat orifice plates on pumping cost for large lines.
Formula
Venturi Meter Flow Calculator is a free venturi meter for process, mechanical and water engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Venturi Meter Flow Calculator
Flow rate through a venturi from inlet/throat diameters and measured pressure drop. The calculation implements Q = C_d · A₂ · √( 2·ΔP / (ρ·(1 − β⁴)) ), β = D₂/D₁ (ISO 5167-4 — Venturi tubes). Venturis recover most of the differential pressure (low permanent loss), which is why they beat orifice plates on pumping cost for large lines.
How to use Venturi Meter Flow Calculator
- 1Enter Inlet diameter D₁ in mm.
- 2Enter Throat diameter D₂ in mm.
- 3Enter Pressure drop ΔP in kPa.
- 4Enter Fluid density in kg/m³.
- 5Read Flow rate, Diameter ratio β instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Venturi Meter Flow Calculator?
- ✓Implements the standard formula — Q = C_d · A₂ · √( 2·ΔP / (ρ·(1 − β⁴)) ), β = D₂/D₁
- ✓Reference cited on-page: ISO 5167-4 — Venturi tubes
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Venturi Meter Flow Calculator use?+
It computes Q = C_d · A₂ · √( 2·ΔP / (ρ·(1 − β⁴)) ), β = D₂/D₁, per ISO 5167-4 — Venturi tubes. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Venturis recover most of the differential pressure (low permanent loss), which is why they beat orifice plates on pumping cost for large lines.
Does this work for any fluid?+
Yes — density and viscosity are inputs (with common fluids suggested in the field hints), so the same physics applies to water, oils, gases and process fluids. Compute always runs in SI internally, so unit mix-ups can't corrupt the result.
Is the Venturi Meter Flow Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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