What My Rig is
Every calculator on this site needs the same handful of numbers: your battery bank, your tanks, your weights, your truck's ratings. My Rig is where they live. Enter them once and every tool opens already knowing your setup; enter a number on any calculator and it lands here. Own more than one rig, or shopping between three? Save them all. The active one is what every tool starts from, and the comparison table puts them side by side against the same truck.
A "600 W" solar array makes about 1.89 kWh on an average day flat on a roof, against the 2.7 kWh that rating times sun hours suggests, because panels lie flat, run hot and lose a little in the wires and the controller. A 20 lb propane cylinder holds about 432,000 BTU. A lead-acid bank gives up 50% of its label before you start shortening its life; lithium gives up 80% in our planning math. Every card above uses those figures, and the calculators call the same engine functions, so a correction to one reaches every page that uses it.
Where the numbers come from
Nothing on this page is a guess of its own. Off-grid days come from your usable watt-hours against a typical day's use (until the Power Budget tool replaces the guess with your appliances), your fresh and gray tanks against gallons per person, and your propane against a furnace duty cycle set by the outside temperature. Shore-power headroom is your service in watts minus the air conditioner's running draw. The towing verdict runs the checks a hitch shop would: loaded trailer against tow rating, hitch weight plus people against the door-sticker payload, the whole combination against GCWR, and the hitch against its own rating. An unweighed trailer is assumed to be at its GVWR, because that's what it weighs the day it matters.
Where to find your numbers
| Field | Where it is |
|---|---|
| GVWR, UVW, CCC, GAWR | GVWR and GAWR are on the certification label (49 CFR 567.4). CCC is on the yellow cargo-capacity label near the entry door (49 CFR 571.110), which counts full propane in the RV's own weight and treats water as cargo. UVW is GVWR minus CCC. |
| Hitch (tongue / pin) weight | The dry figure is on the manufacturer's spec sheet or its own weight sticker, not the federal label; the loaded one comes from a scale. Loaded, expect 10–15% of trailer weight for a travel trailer and 15–25% for a fifth wheel. |
| Truck payload | The tire-and-loading sticker on the driver's door jamb: "the combined weight of occupants and cargo should never exceed …". Use that number rather than the brochure's. |
| Max tow, GCWR | The owner's manual towing section, by engine, axle ratio and cab, or the manufacturer's towing guide for your model year. |
| Receiver rating | Stamped or on a sticker on the receiver itself, two numbers: weight-carrying and weight-distributing. |
| Tank sizes | The spec sheet or the manufacturer's page for your floor plan; also often on the tank-monitor panel's label. |
| Battery Ah, chemistry, max discharge | The battery's own label; the continuous discharge rating is on the data sheet. |
| Inverter and generator watts | The data plate: continuous (not "peak") for an inverter; rated or running watts (not "starting") for a generator. |
| AC BTU and LRA | The data plate under the rooftop shroud, or the spec sheet. LRA (locked-rotor amps) is the starting current a soft start reduces. |
| Furnace BTU | The furnace's own label behind its exterior door, stated as input BTU/h. |
| Tire max load and pressure | The sidewall: "Max load 2,830 lb at 80 psi cold". |
Every field above has a matching hint on the card. The full guide shows each label, plate and sticker line by line, with the lines to ignore.
Your data stays on this device
My Rig lives in your browser's local storage. There's no account, nothing is sent to us, and we couldn't read it if we wanted to. The trade-off: it won't follow you between devices or browsers unless you export it, and clearing your browser data clears it. The button below erases everything this site has stored, immediately and completely.