Frequently asked questions
Everything about the free trial, the standards behind the tools, accuracy, sharing and your account. Still stuck? Email us.
Getting started & pricing
Is MechanixCalc free to use?+
Yes — there is a genuinely useful free tier (the unit converter, reference library, steel/section properties, GD&T and tolerance tools). On top of that, every new account gets a 14-day free trial of ALL 48 calculators and the schematic editors, and anyone can preview the whole suite for 30 minutes with no sign-up at all.
Do I need a credit card to start the trial?+
No. The 14-day trial requires no credit card and no payment details. You simply create a free account and get full Expert access for 14 days. Nothing is charged automatically when the trial ends.
What happens when my 14-day trial ends?+
Your account automatically drops to the free tier — you are never auto-charged. You keep access to the free tools (converter, reference library, steel sections, GD&T and tolerance tools) and can upgrade to a paid plan whenever you choose.
Can I try the tools without signing up?+
Yes. You can preview the full suite for 30 minutes with no account. After that, create a free account to continue with the 14-day no-card trial.
How much does a paid plan cost?+
See the Pricing page for current plans. Billing is handled securely by Paddle (our Merchant of Record); you can cancel at any time and changes take effect at the end of your billing period.
Tools, standards & accuracy
Which tools are included?+
48 standards-based calculators spanning rotating machinery (shafts, bearings, rotor dynamics, flywheels, motors), power transmission (gears, belts, chains, couplings, clutches, press fits), machine elements (bolts, springs, keys, seals, ball screws, cams), structural & stress (beams, columns, fatigue, welds, Mohr's circle, torsion), manufacturing & metrology (machining, sheet metal, tolerance stack-up, GD&T), and fluid & thermal systems (pipe flow, pumps, compressors, heat exchangers, pressure vessels, hydraulics, pneumatics), plus lifting tools — and three schematic editors (fluid power, P&ID and electrical).
Which engineering standards do the calculators follow?+
Each tool states the governing standard(s) in its header — for example ISO 6336 for gears, ISO 281 for bearing life, VDI 2230 for bolted joints, DIN 743 for shafts, EN 1993 (Eurocode 3) for steel, and ASME B31.3 for process piping. The methodology and references are also printed in every PDF report.
Are the results accurate enough to use in real designs?+
Most calculators are standard-validated: they implement a cited governing standard or recognised textbook method, and each is checked against that standard by an automated test suite that re-runs on every release. Every report shows the formulas, substituted values and references so a reviewer can follow the work. That said, the tools are a decision-support aid — not a certified design and not a substitute for engineering judgement. The responsible (chartered/PE) engineer must independently verify any result before it is used for manufacture, construction, procurement or certification. See our Engineering Disclaimer for the full basis on which results are provided.
What does the “≈ Engineering estimate” badge mean?+
A small amber “Engineering estimate — not standard-validated” badge marks panels that use a simplified, heuristic or manufacturer-specific model for which no public governing standard exists. These are reasonable first-pass models for preliminary sizing, but they are not validated to a standard and should not be relied on for a final design. A few tools — notably slewing-ring bearings, shaft couplings and worm gears — are estimate-based and should be verified against the component manufacturer’s own selection data. Everything without the badge is standard-validated.
Does MechanixCalc support both metric and imperial units?+
Yes. Tools accept SI (metric) inputs and many provide imperial equivalents, and the standalone unit converter covers the common mechanical-engineering quantities.
Is there an AI assistant?+
Yes. Every calculator has a built-in AI Engineering Assistant (powered by Claude) that sees your live inputs and results and answers questions about the calculation, the governing standard and how to improve the design. Hourly question limits scale with your plan: Core 10/hr, Pro 20/hr, Expert 50/hr.
Can I use MechanixCalc inside my CAD software?+
We're building CAD add-ins so you can run validated checks without leaving your modeller. The first — a Fusion 360 add-in for Expert users — reads the User Parameters from your active model and calls the MechanixCalc REST API to return validated safety factors right inside Fusion. It's a thin client: all calculation stays server-side on our engines, and it sends only the parameters you choose to run, never your CAD file. Inventor and SolidWorks add-ins are planned next.
Saving, sharing & reports
Can I save my calculations?+
Yes. Signed-in users can save any calculation to their account and reopen it later from the My Calculations page — the inputs and results are stored so you can pick up exactly where you left off.
Can I organise my calculations into projects?+
Yes. Signed-in users can group saved calculations into projects, so everything for one job, machine or assembly lives together, and your dashboard surfaces recent projects with a shortcut to resume where you left off. Projects are private to your account, and deleting a project never deletes its calculations — they simply become ungrouped again.
Can I share a calculation with a colleague?+
Yes. From any saved calculation you can mint a public, read-only share link. Anyone with the link sees a clean, branded summary of the inputs and results — no account required to view it.
Can I export a PDF report?+
Yes. Every calculator generates a branded, multi-page PDF engineering report with a title block, a PASS/REVIEW/FAIL verdict, the cited standard, input and result tables, a worked methodology section (formula → substituted values → result), the tool's schematic sketch embedded as a diagram, plus assumptions, references and a disclaimer — suitable for a design file or submittal. Pro and Expert users can upload their own company logo and name so the report is white-labelled as their deliverable.
Can I export to Excel, or combine several calculations into one document?+
Yes. Every tool exports its inputs and results to Excel (.xlsx). You can also bundle several saved calculations into a single multi-section submittal PDF (the Calculation Package) — a cover page, contents, and one section per calculation.
Account, data & support
How is my data handled?+
We use essential cookies only and do not sell your data. Your saved calculations are private to your account unless you explicitly create a public share link. See the Privacy Policy for full details.
How do I cancel or get a refund?+
You can cancel a paid plan at any time from your account; access continues until the end of the current billing period. Because the trial is free with no card, there is nothing to refund for trial users. See the Refund Policy for details.
Do you offer team or multi-seat plans?+
Yes — the Team plan is $49/seat/month (billed annually, 5–20 seats) and gives every seat full Expert-level access. Set-up is handled by email today (contact us from the Pricing page); a self-serve seat-management dashboard and shared calculation workspace are in development. For more than 20 seats, see the Enterprise option.
Is there a REST API?+
Yes, on the Expert plan. Generate and manage your own API keys (mxc_live_…) from the API docs page, then POST your inputs to /api/v1/<tool> with your key in the x-api-key header to get results back as JSON. No separate onboarding needed — and for security the full key is shown only once, when it's created.
Which browsers are supported?+
MechanixCalc runs in any modern desktop browser (Chrome, Edge, Firefox, Safari). Calculations run server-side, so a current browser and an internet connection are all you need.
Ready to try every tool?
14 days of full access. No credit card. Cancel anytime.