Stay-length planning
Estimate whether power, solar recovery, fresh water, gray tank, or black tank capacity is most likely to end an off-grid stay first.
Quick answer
Cross-system calculator
Solar, battery, fresh water, gray tank, and black tank all get a vote. This tool compares them so you do not improve the wrong system first.
Current result
The weakest system still reaches the 5-day target on paper. Keep a weather, water, and dump-station buffer before treating that as a guarantee.
Practical stay
5.0 days
Usable battery
2.2 kWh
Avg harvest
1.9 kWh/day
Open the water calculator next and test lower shower, dishwashing, cooking, and refill assumptions.
Verify the stay
First thing to check
5.0 days
40 gallons divided by 8 gallons/day for the whole crew.
Lower daily gallons, carry separate drinking water, add portable containers, or plan a refill before this day.
Next system to watch 2
7.0 days
35 gallons divided by 5 gallons/day from dishes, showers, and sink use.
Use basin dishwashing, shorter showers, outdoor rinse routines where legal, or schedule a dump stop sooner.
Next system to watch 3
25.0 days
30 gallons divided by 1.2 gallons/day from toilet use and flush water.
Use less flush water, confirm tank capacity, or plan a dump stop before black tank margin gets uncomfortable.
Next system to watch 4
30.0 days
Average solar harvest covers the entered daily load on good-sun days, so power is not the first paper limiter.
Reduce daily watt-hours, add solar, add usable battery, or plan generator/alternator recovery before the bank gets low.
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A printable cross-system stay snapshot that keeps the first thing to check, power recovery, tank pressure, and next checks together.
Quick answer
First thing to check
Fresh water at 5.0 days
Practical stay
5.0 days
Assumptions and confidence
Biggest answer movers
Planning boundary
This estimate does not replace weather judgment, road access checks, legal stay limits, safe drinking-water reserve, dump-station planning, or electrical installation review.
Prefilled stay-length scenarios
These scenarios compare power, solar recovery, fresh water, gray tank, and black tank limits for ordinary RV travel patterns.
Short trip baseline
Weekend Couple Starter
Best first pass when you need to know which system ends the trip first.
Load this profileWorkday-capable profile
Remote Work Desert Week
Best first pass when you need to know which system ends the trip first.
Load this profileLower-sun profile
Shoulder-Season Forest Camp
Best first pass when you need to know which system ends the trip first.
Load this profileMore people, faster tanks
Family Dry-Camping Long Weekend
Best first pass when you need to know which system ends the trip first.
Load this profileLean system profile
Minimal Van or Small Trailer
Best first pass when you need to know which system ends the trip first.
Load this profileWant the reusable trip-readiness version?
Printable off-grid RV binder for rig profile, departure checks, tank and propane planning, camp arrival, reset days, pack-up, fallback sites, and seasonal prep.
Delivered as a printable PDF packet, tablet-friendly Markdown pages, CSV planning sheets, and single-page quick checks. Instant Lemon Squeezy checkout opens directly. Receipt and file access go to the checkout email.
Make the 72-hour window less chaotic.
Know what could cut the stay short before you leave.
What it adds
$39A working trip binder for the garage or tow vehicle
Cleaner handoffs between driver, setup, and indoor tasks
Less forgotten friction before departure, arrival, reset day, and pack-up
Better continuity from one trip to the next
Inside at a glance
Binder setup page, active trip packet control, rig profile, 72-hour departure checklist, arrival, reset-day, and pack-up routines
Tank, propane, refill, fallback-site, shared handoff, maintenance, and quick-check pages
Seasonal inserts for heat, cold, shoulder season, wind, smoke/fire restrictions, freeze, rain/mud, desert, mountain, and coastal trips
What this adds
A stay-length estimate is useful when you are deciding what to improve next. If the gray tank is the first limiter, buying another battery is solving the wrong problem.
Tune the power system
Use this when power recovery or battery reserve is the shortest limit.
Run the RV solar calculatorTune the water system
Use this when fresh water, gray water, or daily habits are the shortest limit.
Run the RV water calculatorRead the stay-length guide
Use the guide when you need rules, land access, resupply, and practical trip pacing.
Read the boondocking stay-length guideLimiter map
Compare
Compare fast
Use one comparison matrix to scan the practical differences. Small screens stack each row; wider screens keep the first column pinned.
| Spec | What it means | Best next move |
|---|---|---|
| Power recovery | Daily load is outrunning average solar harvest and usable battery reserve. | Reduce Wh/day, add solar, add battery, or plan generator/alternator recovery. |
| Fresh water | The crew's gallons/day burns through the fresh tank before the target stay ends. | Use the water calculator, carry separate drinking reserve, or plan a refill. |
| Gray tank | Sink, shower, and dishwater capacity ends the stay before fresh water does. | Change dishwashing and shower routines or plan a dump stop sooner. |
| Black tank | Toilet use and flush water create the first waste-capacity limit. | Confirm tank size, adjust flush habits, or shorten the dump interval. |
Stay-length math
The tool compares usable battery reserve after solar harvest, fresh-water burn rate, gray tank fill rate, and black tank fill rate. The shortest limit is the one to fix first.
Usable battery watt-hours are compared against the daily power gap after average solar harvest. If solar covers the daily load on good-sun days, power is not treated as the first paper limiter.
Fresh tank days are tank gallons divided by total daily gallons for the crew. This keeps the estimate tied to actual habits instead of a generic per-person number.
Gray and black tank days are calculated separately because either tank can end a stay before fresh water or battery reserve does.
Avoid these traps
Adding solar does not help if gray tank capacity ends the trip on day four. This calculator ranks the trip limits before you spend money.
Good-sun harvest is an average planning number, not a weather promise. Shade, dust, heat, clouds, and campsite orientation can all move the power result.
A rig may be able to stay ten days on paper, but land-manager rules, road conditions, water source closures, and dump access still control the real plan.
Treat the calculator result as a planning range, then verify the relevant manufacturer guidance, safety limits, installation requirements, and local rules before changing the rig.See assumptions
Gear to compare after the math
These handoffs match the calculator family, not a one-click prescription. Verify fit, specs, clearances, and install limits before buying.
Camco TastePURE Water Filter
Best for
Basic refill hygiene on normal campground or service-stop fills
A simple first handoff when the calculator result says refill quality and speed matter more than a tank upgrade.
Current listing
Camco TastePURE Water Filter at Camco.
Reliance Aqua-Tainer 7 Gallon
Best for
Adding portable reserve without rebuilding the plumbing
A jug-style reserve makes sense when the water result is close but one extra refill buffer changes the trip.
Current listing
Reliance Aqua-Tainer 7 Gallon at Reliance.
Clearsource Premier RV Water Filter System
Best for
Higher-flow filtration for regular refill routines
Consider this class when the water plan depends on frequent fills and you want better flow than a small inline filter.
Current listing
Clearsource Premier RV Water Filter System at Clearsource.
Frequently asked
No. Use this calculator to find the first limiter. Then open the detailed calculator for that system and tune the assumptions before buying gear.
Waste capacity is often the overlooked stay-length limit. A fresh tank can look fine while gray water or black water forces a dump stop first.
Check the daily watt-hour estimate first. If the load is real, compare adding solar, adding battery, reducing inverter use, or planning generator/alternator recovery.
Keep at least one day of drinking water separate from normal wash water, and avoid planning battery discharge down to the edge. Treat this result as a planning range, not a guarantee.