RV & Camper Battery Calculators
Plan your RV or camper battery system with engineering-grade tools. Size house batteries for boondocking, estimate runtime for appliances, and match inverter loads to battery capacity.
RV battery systems must balance three constraints that rarely coexist in stationary applications: limited space, limited weight, and the need for reliable off-grid power. Unlike home backup systems where battery size is constrained only by budget, RV installations must fit within the vehicle's weight capacity and available compartment dimensions.
The first step in RV battery design is cataloging every electrical load you plan to run. Common RV loads include LED lighting (10–20W total), a 12V compressor fridge (40–60W continuous, 200–400 Wh/day), water pump (intermittent), ventilation fans (5–15W each), phone and laptop charging (50–100 Wh/day), and entertainment systems (50–200W). For campers with microwaves, coffee makers, or air conditioning, you will need a significant inverter and battery bank.
System voltage selection impacts both cost and performance. A 12V system is the most common and compatible with the widest range of RV appliances and accessories. For larger systems exceeding 2 kW of continuous load, 24V reduces current draw by half, allowing thinner wiring and reducing voltage drop. Our calculators help you evaluate the trade-offs between 12V and 24V configurations for your specific load profile.
Lithium LiFePO4 batteries have become the standard for serious RV applications. Their 80–90% depth of discharge means you can use nearly the full rated capacity without damaging cycle life. A 200Ah 12V LiFePO4 battery provides 2,048 Wh of usable energy at roughly 50 lbs, compared to a lead-acid bank requiring 400Ah (and 130+ lbs) to deliver the same usable energy at 50% DoD.
Available Calculators
RV Battery Calculator
Calculate the battery bank size you need for your RV or camper. Estimate daily consumption and required capacity for your camping trips.
Inverter Battery Calculator
Calculate the battery capacity you need for AC inverter loads with DoD and efficiency adjustments.
Camper Battery Runtime
Estimate how long your camper battery will run lights, fridge, fans, and devices while boondocking.
Inverter Battery Matching
Convert between Ah and Wh to match your inverter load requirements with battery capacity.
RV & Camper Guides
RV Battery Sizing Guide
LEARNING CENTERCamper Battery Runtime Guide
LEARNING CENTERVan Life Battery Planning
LEARNING CENTERHow Many Batteries for RV?
LEARNING CENTERRV Lithium Battery Guide
LEARNING CENTERHow to Size a Battery Bank
LEARNING CENTERBattery Sizing Reference
LEARNING CENTERLiFePO4 Voltage Chart
LEARNING CENTERBest Battery Chemistry for RV
LEARNING CENTER12V vs 24V RV Batteries
Frequently Asked Questions
How many batteries do I need for my RV?
For weekend camping, a single 100Ah 12V LiFePO4 battery typically provides enough power for lights, water pump, phone charging, and a small fridge. For full-time RV living or extended boondocking, 200–400Ah at 12V (or a 24V system) is recommended to power appliances like microwaves, coffee makers, and entertainment systems.
What is the best battery chemistry for RV use?
LiFePO4 (Lithium Iron Phosphate) is the recommended chemistry for RV applications. It offers 80–90% usable capacity (vs 50% for lead-acid), 3000–5000 cycle lifespan, 50% weight reduction, and zero maintenance. The higher upfront cost is offset by 3–5x longer service life and superior performance in RV environments.
Should I use a 12V or 24V system in my RV?
12V is standard for most RVs and compatible with the widest range of appliances and accessories. 24V becomes advantageous for larger systems (over 2 kW) because it halves the current, reducing wiring costs and voltage drop. If you are building a new system from scratch with significant power needs, 24V is worth considering.
How long will my RV battery last while boondocking?
Runtime depends on your battery capacity and daily load profile. A typical weekend camper with a 100Ah LiFePO4 battery running lights (50W), a fridge (60W), water pump (intermittent), and phone charging can expect 2–3 days between charges. Full-time boondockers with 300Ah+ systems and solar panels can go indefinitely with careful load management.
Do I need solar panels for my RV battery system?
Solar panels are highly recommended for RV battery systems, especially for extended boondocking. A 200–400W solar array can replenish 600–1200 Wh per day, covering the daily consumption of most moderate RV setups. Without solar, you would need to run a generator or drive to recharge, both of which have limitations.