- Everything here is free and provided as information, not as professional electrical, mechanical or towing advice.
- We work hard to be accurate, and the ratings printed on your stickers and data plates still win.
- Never exceed a weight rating (GVWR, GCWR, axle, tire, hitch or receiver) or a component's electrical rating. Those rules outrank anything a calculator tells you.
- Your rig, your truck and your trip are your responsibility. We can't see any of them.
Who these terms are with
RVingToolbox (rvingtoolbox.com) is operated by Hamilton Digital Media Limited, registered in England and Wales under number 15608219, registered office 13a Mill Lane, Wimborne, Dorset, BH21 1LN, United Kingdom. In these terms, "we" and "us" mean that company. By using the site, you're agreeing to what follows.
What this site is
A set of free calculators for RV owners: power and solar, water and propane, weights and towing, trip costs. There's nothing to buy from us, no account to create, and no subscription. You can use the tools for your own rig, or for rigs you work on professionally, at no charge.
What we promise about the math, and what we don't
We take the numbers seriously, because they're the entire point of the site. The formulas and constants come from published sources (electrical code conductor tables, the federal weight-label rule, manufacturer data sheets and data plates, NASA and NREL solar data) rather than copied from someone else's blog. All the calculators share common calculation engines, so they can't disagree with each other. Those engines are covered by an automated test suite with hand-worked expected values, and every result has a "show the math" panel so you can follow the arithmetic yourself.
What we can't do is see your rig. A calculator only knows what you type into it, and every output here is a starting point, not a certification: batteries age, generators derate with altitude and heat, trucks leave the factory with options that change their ratings, and no formula captures a badly loaded trailer. You remain responsible for checking a result against the ratings printed on your equipment and your own judgment before acting on it. If a result looks wrong, it might be, please tell us.
- Weight ratings are limits, not targets. GVWR, GCWR, each axle's GAWR, tire load ratings, and the hitch and receiver ratings: whichever you reach first wins. A calculator that says "fine" does not override a sticker that says otherwise.
- Electrical ratings are limits. Breakers, wire gauge, inverter and battery discharge ratings, shore-power service. Overloading any of them is a fire risk, not a rounding error.
- Propane and generator work belongs to competent hands. Gas fittings, regulators, and anything that changes how exhaust or fumes move deserve a qualified technician. Keep working carbon-monoxide and propane detectors in the rig.
- Weigh, don't estimate, before you tow far. A CAT scale ticket beats any calculation of loaded weight, including ours.
- Manufacturer instructions win. If a maker's documentation differs from anything here, follow the maker.
This isn't professional advice
The site is general information, not tailored advice for your rig, and using it doesn't create a professional relationship between us. Towing numbers are arithmetic on ratings you supply, not an inspection of your setup. Electrical sizing is a starting point for a design a qualified person should check, not an installation instruction. Cost tools are estimates from your inputs, not financial advice.
What stays your responsibility
- Reading the ratings on your RV's weight label, your vehicle's door-jamb sticker, your tires and your hitch before applying any number from this site.
- Entering accurate inputs. A calculator is only as good as the tank size, battery capacity and weights you give it.
- Driving and towing within your ability, your local laws (including brake-controller and toad-braking requirements), and your equipment's ratings.
- Having electrical, propane and hitch work done or checked by someone competent to do it.
- Deciding whether a given result makes sense for your rig before acting on it.
Links to other sites
We link out to retailers, manufacturers and reference sources. Some of those may be affiliate links, explained in full in our affiliate disclosure. We don't control other websites and aren't responsible for their content, their products, or their privacy practices; once you leave here, their terms apply.
Content and copyright
The writing, design, code and calculator implementations on this site belong to us. You're welcome to use the tools, quote us with credit and a link, and print or save results and charts for your own use. Please don't republish our articles wholesale, copy the calculators onto another site, or scrape the site automatically.
To be clear about what we're not claiming: the underlying formulas, standards and constants are public knowledge and nobody owns them. The electrical code tables, the weight-rating definitions and the energy content of propane are free for anyone to use; it's our particular expression of them that's covered.
Availability
We aim to keep the site up and current, but it's provided as-is. We may change, move or retire tools and articles, and we don't guarantee uninterrupted access.
Liability
To the extent the law allows, we're not liable for loss or damage arising from your use of this site, including damage to an RV, a tow vehicle or their components, purchases made on the strength of a calculation, or losses from acting on a result without checking it against your equipment's ratings.
Nothing in these terms limits or excludes our liability for death or personal injury caused by our negligence, for fraud, or for anything else that can't lawfully be excluded. If you're a consumer, you keep all the statutory rights you have where you live, and nothing here takes them away.
Governing law
These terms are governed by the laws of England and Wales, and disputes fall to its courts. If you use the site as a consumer somewhere else, you keep the protection of any mandatory consumer law that applies where you live.
Changes
We may update these terms as the site grows. The date at the top of this page shows when they last changed materially, and continuing to use the site means the current version applies.
Contact
Questions about these terms: [email protected]. Something here that's factually wrong: [email protected].