Plumbing Formulator vs testo Combustion App
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Plumbing Formulator
This professional calculator app provides over 200 formulas, calculators, and reference materials for plumbers, HVAC technicians, and mechanical contractors. It covers a wide range of calculations for water flow, piping, drainage, water heaters, pumps, and more, all in one pocket-sized tool.
- Over 200 formulas and calculators
- Water flow and supply calculations
- Pipe and piping calculations
- Drainage and venting calculations
- Water heater and pump calculations
- Reference charts and code books
- Pipe cut list optimizer
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PLUMBING FORMULATOR is the ultimate professional calculator for plumbers, HVAC techs, and mechanical contractors. Over 200 formulas, reference charts, code books, and pro tools in your pocket. CALCULATORS AND FORMULAS Water Flow and Supply: pipe velocity, flow rate, GPM, fixture unit demand, and supply sizing. Pipes and Piping: area, volume, and weight for copper, steel, cast iron, and plastic. Hazen-Williams friction loss, pressure ratings, and 45 degree offsets. Drainage and Venting: drain sizing, slope and fall, vent sizing, fixture units, and wet vents. Water Heaters: BTU requirements, recovery rates, tank sizing, first hour ratings, and hot water demand. Pumps and Pressure: water and brake horsepower, efficiency, head pressure, velocity head, and PSI to feet of head. Storm Drainage: roof drains, rainfall intensity, gutter and leader sizing, and retention. Gas Piping: size natural gas and propane lines, BTU loads, pressure drop, and appliance demand. Medical Gas: size oxygen, nitrogen, nitrous oxide, and medical air. Vacuum demand and manifolds per NFPA 99. Swimming Pools: volume, fill time, pump sizing, turnover, evaporation loss, and main drains. Septic and Sewage: septic tanks, leach fields, and sewage pump capacity. Thermal Expansion: expansion tank sizing, system pressure, and pipe length changes. REFERENCE MATERIALS Charts and Tables: dozens of reference charts including pipe sizing, fixture units, and materials in PDF. Massachusetts Plumbing Code: complete 248 CMR reference with all chapters. Plumbing Design Guide: a 24 chapter design and installation guide. Technical Drawings: professional diagrams and installation details. TOOLS AND FEATURES Pipe Cut List Optimizer: enter lengths and stock sizes for an optimized cutting plan that cuts waste. Unit Conversions: length, area, volume, flow, pressure, temperature, weight, and power. Geometry Calculators: area and volume for circles, rectangles, triangles, cylinders, spheres, cones, and more. BUSINESS MANAGEMENT More than a calculator. Tap Business to run your service company from the same app. Customers: contacts, service addresses, job history, and outstanding balances. More than a calculator. Tap Business to run your service company from the same app. Customers: contacts, service addresses, job history, and outstanding balances. Quotes and Estimates: build quotes on site and turn an approved quote into an invoice with one tap. Invoicing: branded invoices with your logo, parts and labor, taxes, and terms. Send by email, print, or PDF. Payments: cash, check, card, ACH, or credit. Apply one payment across invoices and manage credit automatically. Scheduling: book service calls, track jobs, and set up recurring contracts that auto-generate invoices. Business Reports: balances, receivable aging, revenue, and payment history. Export as CSV or PDF. Business features are a separate one-time upgrade, discounted for existing Bill-Craft and ServiceBoss customers. PLUMBING PRO FEATURES Upgrade to Plumbing Pro to save calculations with full detail, export results, keep unlimited history, and remove ads. One time purchase with lifetime access. A modern dark interface built for the job site, with breakdowns showing the steps and formulas behind every result. Perfect for plumbers, apprentices, HVAC techs, mechanical engineers, and building inspectors. Download Plumbing Formulator today and put professional plumbing calculations at your fingertips.
testo Combustion App
Control your testo 330 flue gas analyzer remotely from your smartphone or tablet. Create and send professional PDF reports with photos and your logo directly from the field, ensuring fast and efficient documentation.
- Remote start/stop of measuring instrument
- Intuitive touchscreen menu
- Graphical trend view
- PDF report creation
- Export measurement values to CSV
- Customizable reports with logo
- Bluetooth connectivity (20m range)
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The App for controlling the testo 330 flue gas analyzer and for report creation on site Install our free App on your Smartphone/tablet, and start / stop your testo 330 right where you happen to be. The report, with photos, can be sent to your office or directly to the customer as a simple and fast documentation, right after the measurement! - Start and stop of the measuring instrument via Smartphone and tablet - Easy and intuitive menu guide in the touchscreen - Track changes using the graphical trend view - The measurement values always in view during the adjustment of the system. - Creation of PDF reports or export of measurement values in csv (Excel) - Create reports with your own logo - Range of approx. 20 m without obstruction via Bluetooth This app can be used with the testo 330 flue gas analyzer with bluetooth low energy module only!!
Screenshots
Verdict
The clearest difference is rating: Plumbing Formulator at 4.6 against testo Combustion App's 1.4. Plumbing Formulator also leads on update cadence (every 2 months vs every 7 months). testo Combustion App's advantage is in-app purchases (none vs 4) and iOS requirement (9.3 vs 18.6). On price, review sentiment, ratings volume and ads there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Plumbing Formulator sells 4 one-off in-app purchases. testo Combustion App asks for nothing beyond the download.
Plumbing Formulator holds the better App Store score, 4.6 against 1.4. Both are backed by a comparable volume of ratings — 7 and 10 respectively. Written reviews complicate that: 9% of Plumbing Formulator's written reviews are positive against 13% of testo Combustion App's, so the app with the better star average is not the one people write more warmly about.
Plumbing Formulator ships an update every 2 months, testo Combustion App every 7 months. The most recent releases landed on October 31, 2026 and October 29, 2026 respectively.
| Parameter | Plumbing Formulator | testo Combustion App |
|---|---|---|
| Price | Free | Free |
| Rating | 4.6 (7 ratings) — better | 1.4 (10 ratings) |
| Positive reviews | 9.1% of reviews | 12.8% of reviews — better |
| Number of ratings | 7 | 10 — better |
| Update frequency | Every 2 months — better | Every 7 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free | Free |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 18.6 | 9.3 — better |
| Further details — not scored | ||
| Size | 123 MB | 62 MB |
| Age rating | 4+ | 4+ |
| Developer | Historycentral.com | Testo SE & Co. KGaA |
Customer experience
Plumbing Formulator
testo Combustion App
In-app purchases
Plumbing Formulator
- Pro Version$1.99
- Pro Purchase$3.99
- Starter$5.99
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- Growth$9.99
testo Combustion App
No in-app purchases
Questions
Is Plumbing Formulator free?
Is testo Combustion App free?
Which has better reviews, Plumbing Formulator or testo Combustion App?
Do Plumbing Formulator or testo Combustion App have ads?
Which is updated more often, Plumbing Formulator or testo Combustion App?
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