utility

Engineering Calculator

Run 80 engineering calculations across mechanical, fluids, thermal, electrical, and related fields with unit conversion and parameter comparison in the browser.

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Local processing

About your filesFiles and content selected in this tool are processed in your browser and are not uploaded to a Browser Kitty backend.

Operation demo See the basic workflow in a short video.

About this tool

Engineering Calculator collects recurring engineering calculations for mechanical design, manufacturing, fluids, thermal work, electrical work, tolerances/fits, and unit conversion in one browser tool. Search by formula name or keyword, enter values in practical units, and review results without switching between separate calculators.

The tool keeps assumptions, cautions, and formulas close to each result rather than presenting a number without context. A parameter-sweep view can vary one input over a range and show the numerical trend as a graph and CSV. Saved inputs and history stay on the device, and normal calculations do not send conditions to a server.

Good for

Quickly check approximate beam, shaft, bolt, gear, spring, or bearing calculations during mechanical design
Run common fluid, thermal, or electrical formulas while switching between practical input and result units
Use tolerance/fit, H7/g6, and bolt-size helpers to cross-check manual calculations
Vary a dimension, load, or other input to see how the result changes across a range of conditions

What it can do

Key capabilities available in this tool.

80 engineering calculations across mechanical basics, rotation, bolts, shafts, beams, gears, springs, bearings, fluids, thermal, electrical, and related fields
Find formulas using Japanese/English search, categories, favorites, and recently used calculations
Switch input/output units and review formulas, assumptions, and cautions alongside results
Input helpers for representative materials, M3–M24 metric coarse bolts, and ISO 286 H7/g6 fits
Parameter sweeps across 11, 21, or 51 samples with an SVG trend graph
Copy results, full input conditions, or CSV samples and create explicit fragment-based condition links

How to use

Choose a calculation from search or a category. On desktop, Ctrl/⌘+K or / focuses search.
Enter the required values and switch input/result units as needed. Results update with the current inputs.
Read the assumptions and cautions below the result, and open the formula/details section when you need to verify applicability.
Favorite recurring calculations and optionally use material, bolt, or fit helpers where available.
For trend checking, open the parameter sweep, choose a range and sample count, then review the graph or CSV. Generate a condition link only when you explicitly want to share the current setup.

Supported

Calculation areas include mechanical basics, rotation/power, bolts, shafts, beams, gears, springs, bearings, fluids, thermal, electrical, tolerances/fits, and unit conversion for 80 calculations in total.
Input helpers include representative values for steel, stainless steel, aluminum alloy, copper, and brass; M3–M24 metric coarse bolts; and ISO 286 H7/g6 for basic sizes from 1 to 500 mm.
Display precision can be automatic or 3, 4, or 6 significant digits without changing internal calculation precision.
Parameter sweeps support 11, 21, or 51 samples with ±10%, ±20%, ±50%, 0.5–2×, or custom ranges.
Copy results, conditions, and CSV samples, and explicitly create a URL-fragment condition link containing the current calculation, values, and units.

Limitations and notes

Results are general engineering calculations and do not replace applicable standards, formal design procedures, safety review, or legal requirements.
Material presets are representative values; verify actual grade, heat treatment, temperature, and manufacturer data for the real design.
H7/g6 and bolt-size presets are input helpers and do not automatically determine tolerance systems, strength classes, or joint conditions.
Some inputs such as bearing factors, allowable stress, friction coefficients, and pipe roughness must come from the actual design conditions or manufacturer data.
Beam, spring, bolt, fluid, thermal, and other formulas use simplifying assumptions; check that the displayed assumptions match the real problem.
Parameter sweeps show numerical trends only and do not perform optimization, FEA, CFD, fatigue assessment, or standards compliance checks.

Frequently asked questions

Are calculation inputs sent to a server?

No. Normal calculations, history, favorites, parameter sweeps, and graphs run in the browser. Only an explicitly generated condition link puts the current values and units in the URL fragment.

Can I use the result directly as a final design value?

Treat it as a general-formula check or estimate. Review the displayed assumptions and verify standards, manufacturer data, safety factors, and real boundary conditions before final design.

Does changing units or display digits reduce calculation precision?

No. Unit selection and significant-digit settings affect presentation; they do not intentionally reduce the internal calculation precision.

What is the parameter sweep for?

It varies one input over a range so you can inspect the direction and magnitude of result changes. It is not an automatic optimizer.

Offline version and source code

The distributed HTML has no runtime external dependencies and can be saved and opened directly in a browser. Calculations, search, history, graphs, and CSV generation run locally.

View source on GitHub