O vs Hydraulic Calculator Engineer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
O
This app provides a comprehensive offline tool for selecting standard rubber seal sizes, including O-Rings, X-Rings, and Back-Up Rings. It offers dimension searches, housing calculations for various sealing applications, and supports multiple international standards in both metric and imperial units.
- Offline standard rubber seal size selection
- Search for O-Ring, X-Ring, and Back-Up Ring sizes
- O-Ring housing calculations for sealing applications
- Supports multiple international standards (AS568, METRIC, JIS, etc.)
- Metric and Imperial unit support
- Substitutable O-Ring size suggestions
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GMORS O-Ring Master is the completed tool for standard rubber seal sizes. When you use this APP, you don't need to have internet and catalog. Except O-Ring sizes, it also includes the search functions of X-Ring and Back-Up Ring. Otherwise, you can also use O-Ring Housing to choose suitable O-Ring in your application. Main functions are as follows: Dimension Search:O-Ring, X-Ring and Back-Up Ring. - MM and Inch are both available. - Full standard O-Ring series: AS568, BS 4518, GB/T 3452.1, JIS B2401 P, JIS B2401 G, JIS B2401 S, JIS B2401 V, SMS 1586 and METRIC. - Collocated Back-Up for AS-568 O-Ring. - Substitutable O-Ring sizes within tolerance are available. O-Ring Housing: Piston Sealing、Rod Sealing and Face Sealing. - MM and Inch are both available. - Support calculation for both Static and Dynamic sealing applications (Face sealing is with static calculation only). - Up to 7 O-Ring standards ( AS568, METRIC, JIS B2401 P/G/S/V, JASO F404, GB/T 3452.1, BS 4518 and SMS 1586) for most of size requirement of different groove design.
Hydraulic Calculator Engineer
This app offers a suite of hydraulic calculations for technicians and engineers. It simplifies complex hydraulics by automatically computing results based on user-entered values, eliminating the need for manual formula application.
- Cylinder Calculation
- Power Calculation
- Pressure Difference
- Piston Diameter
- Speed Calculation
- Lifting Time
- Volume Flow
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Hydraulic Engineer Calculators is a practical hydraulic engineering calculator and formula app for engineers, technicians, students, contractors, operators, and anyone working with fluid flow, pipes, pumps, pressure, open channels, hydraulic cylinders, or fluid mechanics. Quickly enter your values, select units, calculate an estimate, review result details, and check the formula used. Hydraulic calculators included: Flow & Pipe Calculators - Pipe Flow Velocity - Calculate fluid velocity from flow rate and pipe diameter - Flow Rate - Calculate volumetric flow from flow area and average velocity - Required Pipe Diameter - Estimate pipe diameter from design flow and velocity - Reynolds Number - Calculate Reynolds number for internal fluid flow Head Loss Calculators - Darcy-Weisbach Head Loss - Estimate pipe friction head loss - Hazen-Williams Head Loss - Estimate water pipe friction loss - Minor Loss - Calculate losses from fittings, valves, entrances, exits, and components Pressure & Head Calculators - Pressure to Head - Convert pressure to hydraulic head - Head to Pressure - Convert hydraulic head to pressure - Hydrostatic Pressure - Calculate pressure caused by fluid depth - Bernoulli Total Head - Calculate total hydraulic head Pump Calculators - Pump Power - Estimate hydraulic pump power from flow, head, and efficiency - Pump Head from Pressure - Calculate pump head from pressure difference - NPSH Available - Estimate Net Positive Suction Head Available Open Channel Flow Calculators - Manning Rectangular Channel - Estimate rectangular channel flow - Froude Number - Calculate the Froude number - Critical Depth - Estimate critical water depth - Orifice Flow - Calculate fluid discharge through an orifice Hydraulic System Calculators - Water Hammer Pressure - Estimate pressure rise from a rapid velocity change - Hydraulic Cylinder Force - Calculate cylinder force from pressure and piston area - Hydraulic Cylinder Speed - Calculate piston speed from flow rate and bore diameter Fluid Properties Calculator - Specific Gravity - Calculate specific gravity from fluid density Useful for: - Hydraulic engineering - Fluid mechanics - Pipe flow and pipe sizing - Water flow and pressure - Head loss and pipe friction - Pump systems and pump power - NPSH calculations - Open channel flow - Hydraulic cylinders - Water hammer - Irrigation, plumbing, water, and wastewater systems - Civil and mechanical engineering Supported units include: - m, mm, cm, ft, in - m², cm², mm², ft², in² - m³/s, m³/h, L/s, L/min, US gpm, ft³/s - Pa, kPa, MPa, bar, psi - m/s, ft/s - W, kW, hp Built-in formula guide Each calculator includes its formula, and the app links to a Hydraulic Engineer Guide with additional information about formulas, variables, units, calculation steps, practical uses, and important considerations. Selected calculators also include dynamic diagrams to help visualize values used in pipe, pressure, head, open channel, tank, and hydraulic cylinder calculations. Simple workflow: - Choose a calculator - Enter your known values - Select units - Tap Calculate - Review the result and details - Check the formula - Open the related guide for more information The built-in search makes it easy to find a specific hydraulic calculator by category or name. Important disclaimer These calculators provide preliminary hydraulic estimates only. Results are not a substitute for professional engineering judgment, certified calculations, manufacturer specifications, site-specific analysis, or applicable codes and standards. Always verify input values, units, fluid properties, pipe specifications, equipment limitations, safety factors, operating conditions, site conditions, and governing requirements before using a calculation for design, procurement, installation, testing, operation, maintenance, or any safety-critical application.
Screenshots
Verdict
The clearest difference is rating: O at 5.0 against Hydraulic Calculator Engineer's 4.3. Hydraulic Calculator Engineer's advantage is ratings volume (9 vs 1) and device support (3 vs 1). On price, update cadence, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.
O holds the better App Store score, 5.0 against 4.3. That said, the two scores are not equally well evidenced: Hydraulic Calculator Engineer has 9 ratings behind it against 1, so its average is the more settled of the two.
O ships an update every 11 months, Hydraulic Calculator Engineer every 22 months. The most recent releases landed on September 22, 2026 and September 10, 2026 respectively.
| Parameter | O | Hydraulic Calculator Engineer |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | 4.3 (9 ratings) |
| Positive reviews | — | 0.0% of reviews |
| Number of ratings | 1 | 9 — better |
| Update frequency | Every 11 months — better | Every 22 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone | iPhone, iPad, iPod — better |
| Requires iOS | 16.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 47 MB | 21 MB |
| Age rating | 4+ | 4+ |
| Developer | GE MAO RUBBER INDUSTRIAL CO., LTD. | Arsosa Network Inc. |
Customer experience
O
Hydraulic Calculator Engineer
In-app purchases
O
No in-app purchases
Hydraulic Calculator Engineer
No in-app purchases
Questions
Is O free?
Is Hydraulic Calculator Engineer free?
Which has better reviews, O or Hydraulic Calculator Engineer?
Do O or Hydraulic Calculator Engineer have ads?
Which is updated more often, O or Hydraulic Calculator Engineer?
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