System curve from one known point or from the pipe, the operating point for 1–4 pumps in parallel or series, and throttle vs VFD vs impeller trim to a target flow, with the yearly energy cost.
USD 29 one-time purchase
Buying several tools? Get the Pumps Complete Kit — USD 129
Need it once? Use it online: check your data free, unlock results from USD 9 for 3 runs.
What it does
System curve two ways
Static head plus K·Q² from one known point, or a pipeline by Darcy with Swamee–Jain friction and fittings.
Operating point
Flow, head, efficiency, power and % of BEP for 1 to 4 pumps, in parallel or in series; what happens when one pump trips.
Flow control compared
Throttle valve, VFD speed and trimmed diameter to reach a target flow, with shaft and electrical power.
Energy cost
Yearly cost of each option and the VFD saving, with motor and VFD efficiencies.
Charts
Pump and system curves with the operating point, and a power comparison bar chart.
Same liquid list
54 pumped liquids, mixtures or your own properties.
Built for engineers
- Visible formulas — nothing hidden, so you can check every step.
- Fully referenced — methods from the standard references, checked against their published worked examples.
- Safe to share — sheets are protected against accidental edits, with an open password so you can still customise.
- Built-in input checks — clear warnings for impossible inputs and values outside typical ranges.
For engineering estimates; verify against site data. Code-based methods are aligned with the publicly documented procedure; they are not a licensed reproduction or a certification.
Preview the workbook
An illustration of the sheet layout of this workbook, not a screenshot of calculated results. Select the image to enlarge it. For questions before you buy, email [email protected].
Specification and checks
| Format | Excel workbook (.xlsx), no macros |
| Version | v1.0 |
| Works in | Excel 2010 or later, Windows and Mac |
| Units | SI, US and British, mixed freely |
| Includes | Guide tab with method and references, calculator, print-ready report |
| Checked against | Operating points for 1 pump, 2 in parallel, 2 in series and a pipeline system match an independent Python model; VFD speed and trim diameters identical. |
| Free version | Try the online calculator |
Online tool or Excel workbook?
| Online tool | Excel workbook (this page) | |
|---|---|---|
| What it does | The same sheet as the Excel workbook, run in your browser | System curve from one known point or from the pipe, the operating point for 1–4 pumps in parallel or series, and throttle vs VFD vs impeller trim to a target flow, with the yearly energy cost. |
| Cost | Check your inputs free. Results: 3 runs for USD 9, or every online tool for USD 15 a month (USD 99 a year) | USD 29 once, yours to keep |
| Input checks and findings | Every input checked; findings with the unlocked results | Every input checked, with findings and recommendations |
| Report for your calculation file | Printable results sheet | Print-ready report with your plant, tag, document number, revision and sign-off |
| Formulas | Method described in the guide | Every formula visible in its cell |
| Save, edit and rerun your cases | Each run separately | Yes: keep and edit your own file |
| Works offline, on a plant PC | No, needs the internet | Yes: Excel 2010 or later, Windows and Mac |
Online access and the Excel workbook are separate licences: one does not include the other.
Compatibility, licence and support
| File | Excel workbook (.xlsx), no macros, version v1.0; works in Excel 2010 or later on Windows and Mac. Sheets are protected against accidental edits, with an open password so you can customise. |
| Licence | Single user. A team licence (up to 5 named users) is 3 × the shop price; site licences on request — licence terms. |
| Updates | Updates to this major version are included; download them again from the link in your receipt. |
| Support | Email [email protected] with your order number — questions on the method, your inputs or your results are welcome. |
| Refunds | If the tool does not work as described, or has an error we cannot fix, email [email protected] with your order number within 14 days of purchase and we will refund you in full. Refunds are not offered for a change of mind once a file has been downloaded. Read the full refund policy. |