Size and verify orifice plates, Venturi tubes, and flow nozzles per ISO 5167. Runs in the browser. Nothing to install. Results update as you type. Shared workspace, not spreadsheets in inboxes.
No account needed to try. No credit card.
From blank form to signed-off calculation in minutes.
Fluid type, pressure, temperature, pipe diameter. Select the tap configuration and what you want to solve for.
Flow rate, bore size, or differential pressure — whichever you chose. Validity flags tell you if you're inside ISO 5167 limits.
Generate a PDF calculation report with all inputs, results, and pipe length tables. Attach it to the project dossier.
FlowCalc traces back to Turbo ORF in the 1980s and FlowCalc32, used by engineers at refineries, steel mills, and paper mills in 40+ countries. The web app is a full rewrite: same verified equations, modern tool.
The calculation is the easy part. Getting it to your team, your dossier, and your next laptop is what takes time.
Runs in any modern browser on Windows, Mac, Linux, or iPad. No admin rights needed. No waiting for IT approval.
Everyone on the team opens the same record. No fourth revision of a spreadsheet from someone's inbox. No wondering if the file you have is the one that was submitted.
IT replaced your laptop? Sign in and keep working. Your calculations and your license live in the cloud, not on a machine.
Updates happen server-side. Nobody is stuck on an old version, and the whole team always runs the same engine.
Most orifice calculations today live in one of two places. Both have problems.
Formula errors hide in cells nobody opens. Versions multiply in inboxes. The person who built it left two years ago, and nobody dares touch column AG.
Exists to sell you that vendor's meters. Installed on one machine, if IT allows it. No shared records, no audit trail, and the assumptions are theirs, not yours.
ISO 5167 calculations that belong to the project, not a person's laptop. Validity flags built in. PDF report ready for the project dossier.
FlowCalc covers orifice plates, Venturi tubes, ISA 1932 nozzles, and long-radius nozzles. Gas, liquid, saturated steam, superheated steam, and water. IAPWS-IF97 steam properties are built in.
Type a value, change a unit, switch fluid type. The result updates immediately. Solve for flow rate, orifice bore, or differential pressure.
Size orifice plates and Venturi tubes during FEED or detailed design. Iterate quickly on bore, tap type, and fluid conditions without touching a spreadsheet.
Verify that an installed meter still meets its original design conditions. Check pipe installation lengths. Flag out-of-range Reynolds numbers before commissioning.
Keep calculation records inside the project, not in someone's inbox. Shareable links, PDF reports, and a consistent calculation engine across the team.
Everything in one place, shared with the team, updated automatically.
Corner tap, flange tap, and D & D/2 tap orifice plates. ISA 1932 and long-radius nozzles. Venturi tubes. Restriction orifice sizing.
Gas, liquid, water, saturated steam, and superheated steam. Density and viscosity computed automatically for steam and water via IAPWS-IF97.
Solve for flow rate, orifice bore, or differential pressure. Auto-recalculates when you change any input. Handles choked flow and cavitation.
Upstream and downstream straight pipe length requirements from ISO 5167-2 Table 3 and ISO 5167-3 Table 1. Both 0% and 0.5% additional uncertainty.
Generate a complete, printable report with all inputs, results, validity flags, and pipe length tables. Ready to attach to a project dossier.
Invite colleagues to your organisation. Everyone sees the same calculations, with the same inputs. The calculation record is the handoff.
$490 per seat per year when you're ready to buy.